Top officials from the United States and the EU met with their Russian counterparts for undisclosed emergency talks in Turkey designed to resolve the standoff over Nagorno-Karabakh, just days before Azerbaijan launched a military offensive last month to seize the breakaway territory from ethnic Armenian control.

The off-diary meeting marks a rare — if ultimately unsuccessful — contact between Moscow and the West on a major security concern, after Russian President Vladimir Putin’s invasion of Ukraine in February 2022 upended regular diplomacy.

A senior diplomat with knowledge of the discussions told POLITICO the meeting took place on September 17 in Istanbul as part of efforts to pressure Azerbaijan to end its nine-month blockade of the enclave and allow in humanitarian aid convoys from Armenia. According to the envoy, the meeting focused on “how to get the bloody trucks moving” and ensure supplies of food and fuel could reach its estimated 100,000 residents.

The U.S. was represented by Louis Bono, Washington’s senior adviser for Caucasus negotiations, while the EU dispatched Toivo Klaar, its representative for the region. Russia, meanwhile, sent Igor Khovaev, who serves as Putin’s special envoy on relations between Armenia and Azerbaijan.

Such high-level diplomatic interaction is rare. In March, U.S. Secretary of State Antony Blinken and Russian Foreign Minister Sergey Lavrov came face to face on the sidelines of the G20 meeting in India — but Moscow insisted the exchange happened “on the move” and no negotiations were held.

In a statement provided to POLITICO, an EU official said “we believe it is important to maintain channels of communications with relevant interlocutors to avoid misunderstandings.” The official also observed Klaar had sought to keep lines open on numerous fronts over the “past years,” including in talks with Khovaev and Russian Deputy Foreign Minister Mikhail Galuzin.

A spokesperson for the U.S. State Department declined to comment on the meeting, saying only that “we do not comment on private diplomatic discussions.”

However, a U.S. official familiar with the matter who was granted anonymity to discuss sensitive diplomatic matters explained the discussions came out of an understanding that the Kremlin still holds sway in the region. “We need to be able to work with the Russians on this because they do have influence over the parties, especially as we’re at a precarious moment right now,” the American official said.

Azerbaijan launched a lightning offensive against Nagorno-Karabakh on September 19, sending tanks and troops into the region under the cover of heavy artillery bombardment. Karabakh Armenian leaders were forced to surrender following 24 hours of fierce fighting that killed hundreds on both sides. Since then, the Armenian government says more than 100,000 people have fled their homes and crossed the border, fearing for their lives.

Azerbaijan insists it has the right to take action against “illegal armed formations” on its internationally recognized territory, and has pledged to “reintegrate” those who have stayed behind. European Council President Charles Michel described the military operation as “devastating,” while Blinken has joined calls for Azerbaijan “to refrain from further hostilities in Nagorno-Karabakh and provide unhindered humanitarian access.”