For decades, the negotiations between the two adversaries were conducted with mediators -- varying combinations of Russia, the United States, and European powers. The influence of powerful global actors, it was thought, was necessary for the two sides to work through their mutual distrust.
Now, though, with Nagorno-Karabakh back in Azerbaijani hands after a swift military offensive in September, Baku and Yerevan have been increasingly conducting their negotiations one-to-one. In December, they reached an unprecedented bilateral agreement to exchange prisoners and for Armenia's support for Azerbaijan's bid to host the COP29 climate conference. Senior officials from the two countries have been holding low-profile bilateral meetings. Diplomats continue to exchange drafts of a peace agreement back and forth and hold occasional meetings of a commission on the Armenia-Azerbaijan border itself, most recently on January 31.
Western involvement, meanwhile, has been put on hold. Azerbaijan has stopped receiving the U.S. and European diplomats who had been trying to shepherd the process along. A meeting between the Armenian and Azerbaijani ministers had been planned for January in Washington, but it never took place, and it's unclear if it will be rescheduled.
"This is an issue between our two countries, and we have to solve it ourselves," President Ilham Aliyev said in a January 10 interview with Azerbaijani media.
"Armenia and Azerbaijan are grown-up enough to tackle the remaining issues by themselves," Elchin Amirbayov, Azerbaijan's senior envoy for special assignments who has been closely involved in the negotiations, told RFE/RL.
Azerbaijanis have argued that the international mediators, at a time of sharpening Russia-West competition around the region, have been increasingly driven by geopolitical motives rather than by concern for peace in the Caucasus. But among Armenians, there is a fear that going it alone will leave them vulnerable to a much stronger Azerbaijan, which regularly suggests that if Armenia doesn't accede to its demands, Baku could use force to impose its will.
Armenian officials argue publicly that talking without mediators is not so significant.
"We have been engaged in negotiations by the facilitation of the European Union, among other facilitators, and nowadays we see that Azerbaijan, unfortunately, refuses to resume the negotiations in the existing frameworks," Foreign Minister Ararat Mirzoian said on January 19.
A bilateral approach works to Armenia's disadvantage, said Benyamin Poghosian, a senior fellow at the Yerevan think tank APRI Armenia. Armenia wants mediators as guarantors for any potential deal, "as power imbalances continue to exist between Armenia and Azerbaijan," and mediators could help balance that out. But the government puts a brave face on it, he argues.
"They understand that bilateral talks will be in Azerbaijan's favor," he said. "But they don't want to show that they have been forced by Azerbaijan to accept the bilateral format."
When negotiations began again in 2022 over a comprehensive settlement to the conflict, two rival tracks emerged: one led by Russia and another by the European Union, backed by the United States. Over time, the political negotiations largely shifted to the Western track, with Russia leading more technical negotiations on border delimitation.
In January, the U.S. envoy to the negotiations, Louis Bono, visited Yerevan but not Baku. Azerbaijani media reported that he was not invited to the capital because the Azerbaijani government had refused to invite him. Later that month, the European Union's top Armenia-Azerbaijan negotiator, Toivo Klaar, also visited Yerevan but not Baku.
Officials in Washington and Brussels have downplayed the snubs, saying that they were related to Azerbaijan's February 7 presidential election and expressing optimism that the Western-mediated talks can continue after that. Aliyev, buoyed by the resounding victory to regain Karabakh last year, is on the verge of winning his fifth consecutive term.
The move to bilateral talks should itself be an encouraging sign, said one Western diplomat familiar with the negotiations, who spoke to RFE/RL on condition of anonymity.
"I really do think that that was significant," the diplomat said, referring to the December 2023 agreement on prisoners and the COP29 conference. "That really signals to us that probably there are more discussions going on than maybe they're publicly talking about. And that's a good thing."
Armenian Prime Minister Nikol Pashinian has alluded to ongoing high-level talks, though details have not been made public.
"Direct contacts between Armenia and Azerbaijan are now more or less active…particularly between my office and the office of the president of Azerbaijan," he said on January 20.
Cutting out the mediators against Armenia's will represents another tactic in Azerbaijan's hardball negotiating strategy, said Shujaat Ahmadzada, a nonresident research fellow at the Baku-based Topchubashov Center, which focuses on international relations and security. Azerbaijan has suspended the Western track "to see whether facilitators will come up with favorable conditions," he said.
The Armenian government is concerned that bilateral negotiations would leave them with no external protection were Azerbaijan to abrogate a peace agreement. But with Azerbaijan holding all the cards, they have little choice but to go along, Poghosian said.
If it didn't accede to the bilateral negotiations, "first, Armenia would be perceived as the nonconstructive side," Poghosian said. "Second, if there are no negotiations, there is a rising possibility of military escalation. So, a decision was made: 'OK, we are not happy with the bilateral format, but if there are only two options -- no negotiations or bilateral negotiations -- then it's better to have the bilateral negotiations.'"
In spite of the downsides for Armenia, Pashinian's government is willing to sign a deal with Azerbaijan for domestic political purposes as well, Poghosian argued.
"The government needs to give some positive news to society," he said, "to show that, 'OK, we know we lost Nagorno-Karabakh, but we are receiving something in return. I told you I will bring peace. Here is the peace.'"
Many in Baku argue that the United States and European Union have disqualified themselves by not being neutral brokers in the conflict.
For one, according to this argument, both Washington and Brussels appear eager to weaken Russia's position in the Caucasus and see the Armenia-Azerbaijan peace process as a means to that end. One of the key unresolved issues is who will provide security on new transportation routes connecting Azerbaijan's mainland to its exclave of Naxcivan through Armenian territory. While Armenia, Azerbaijan, and Russia agreed in 2020 that Russian border guards would do it, Armenia has since soured on Russia and is seeking alternative arrangements. Western diplomats are eager to oblige.
Instead of Russia, possible alternative security arrangements for the transportation routes could be commercial companies or international organizations, the Western diplomat said.
"The American and European goals are much more evenhanded and really want to work toward a durable and dignified peace. I don't know that I could say the same about the Russian intentions," the diplomat said.
Russia, meanwhile, remains keenly interested in having its forces play such a critical role in the Caucasus. In January 18 remarks to the press, Russian Foreign Minister Sergei Lavrov sharply criticized Armenia for trying to back out of the 2020 arrangement.
"The peace treaty process therefore turns into a theater of geopolitical competition between the two rival blocs," said Vasif Huseynov, an analyst at the Azerbaijani government-run Center of Analysis of International Relations. "We may end up with a situation [where] we would create a larger geopolitical conflict in the region while ending a local conflict. Therefore, Baku insists on bilateral talks with Armenia with no involvement of external actors."
Azerbaijanis lately have also claimed that both the United States and Europe have been increasingly taking Armenia's side. One flashpoint recently was a statement by Aliyev, during his January 10 interview, about the border delimitation process that appeared to imply a claim to large swathes of Armenia, including the capital, Yerevan, and the southernmost province of Syunik.
The EU's foreign policy chief Josep Borrell criticized the comments: "Azerbaijan needs to return to substantive peace and normalization talks with Armenia. The latest territorial claims by President Aliyev are very concerning. And any violation of Armenia's territorial integrity will be unacceptable and will have severe consequences for our relations with Azerbaijan."
Borrell "was basically accusing Azerbaijan [of] avoiding or shying away from negotiations, which is complete nonsense," said Amirbayov, the Azerbaijani envoy.
The accusations about territorial claims are meant as a ploy to draw attention away from Armenia's own claims on Azerbaijan, Amirbayov said.
"No one in Azerbaijan has interpreted his words as his intention to go ahead and occupy Armenian territory. These are all just tricks," he said.
Azerbaijani officials have complained that Armenia continues to formally stake a claim to Karabakh in its constitution, the preamble of which makes reference to a 1989 act calling to unify Karabakh with Armenia.
Amirbayov said there are several other such claims in Armenia's formal statements and legislation. For example, when Armenia's legislature ratified the 1991 Alma Ata accords, which accepted Soviet republic borders as the borders of the newly independent states, lawmakers added language saying that it did not apply to Karabakh. He also called attention to language on the Armenian Foreign Ministry website saying that Nagorno-Karabakh is "an integral part of historic Armenia," and recent Armenian filings in the European Court of Human Rights that imply a claim on Azerbaijan.
"We have pointed the attention of the Armenian side to those facts many times, during our [in-person] negotiations, but also through different exchanges of comments," he said. "And the Armenian side acknowledges that this is the fact, but nothing is being done…. When they try to cheat, if I may use the word, if they try to put all the blame and the responsibility on our shoulders, and at the same time in the back of their minds still having these territorial claims against us, it's not going to work," he said.
The Armenian Foreign Ministry declined to respond to RFE/RL's request for comments.
But Foreign Minister Ararat Mirzoian has alluded to the process Amirbayov described. "As part of the peace process, each side has noted problems in the other's legal framework and informed it about that, and both sides have provided relevant clarifications," he told RFE/RL's Armenian Service on January 25. "There will definitely be such discussions."
With or without negotiators, Armenia and Azerbaijan still have to overcome disagreements on other critical issues, including how to demarcate their shared border; determining the fate of several small, Soviet-drawn enclaves; and how to manage new transportation links to Azerbaijan's exclave of Naxcivan. The agreement being negotiated is reportedly short and thin on specifics and aims just to be a framework statement of principles, like mutual recognition of one another's territorial integrity.
Even in a framework agreement, Azerbaijan will continue to push its advantage, research fellow Ahmadzada said.
"What Baku wants right now is full legitimization (not only by Armenia, but also the Western world) of [its full retaking] of Karabakh, along with its other post-2020 goals: access to Naxcivan, enclaves, and border villages," he said. "Now, on all fronts, Baku is showing absolute maximalism, knowing that it is the only actor with huge power disposal at its hand."
Recent signals from Baku, including Aliyev's statements on Yerevan and Syunik, have dampened hopes in Armenia that any sort of agreement will be signed soon, despite the continuing exchanges of draft agreements.
"Unfortunately, after this positive step of the December 8 [bilateral agreement], we saw that Azerbaijan is not continuing with its constructive stance, to say the least," Mirzoian said on January 24. "That manifested itself through both the seventh Azerbaijani proposals on the treaty and the Azerbaijani president's latest interview. There was a significant regression and even a blow to the peace process on a number of key issues."
"How serious is Azerbaijan about this agreement, or is it basically just another way of asking the Armenians to ratify on paper what Azerbaijan wants, with the threat of force hanging in the background?" asked Thomas de Waal, a senior fellow at Carnegie Europe. "That's the hardest thing to know."
Foreign diplomats following the process are trying to remain optimistic. The Western diplomat said there was hope that the European and U.S. mediation may resume after the Azerbaijani elections.
But analysts are not so confident that the multilateral process will resume, at least in anything more than a token format.
"I'm skeptical," de Waal said. "It suits [Azerbaijan] better just to keep the outsiders at a distance."
"[The bilateral talks] is the process now," he said. "This is what's left, and if this doesn't work, then we're in big trouble."