As the United States is set to host Armenian Foreign Minister Ararat Mirzoyan, Washington announced support for peace between Armenia and neighboring Azerbaijan.

Over the weekend, U.S. Secretary of State Antony Blinken spoke over the phone with Azerbaijani President Ilham Aliyev and Armenian President Nikol Pashinian about the peace talks between the two countries. He pledged continued U.S. support to the process.

"Secretary Blinken shared his belief that peace was possible" during his phone call with Aliyev, State Department spokesperson Matthew Miller said in a statement Sunday. "He also expressed the U.S.' deep concern that Azerbaijan's establishment of a checkpoint on the Lachin corridor undermines efforts to establish confidence in the peace process and emphasized the importance of reopening the Lachin corridor to commercial and private vehicles as soon as possible," Miller added. The area is the only land link between Armenia and the disputed Nagorno-Karabakh enclave.

Under the Russia-brokered cease-fire that ended the 2020 conflict, Azerbaijan is required to guarantee safe passage on the Lachin corridor, which Russian peacekeepers patrol. Accordingly, Azerbaijan set up the checkpoint in the area in April "to prevent the illegal transportation of manpower, weapons, mines." Azerbaijani officials have announced that the checkpoint "shall be implemented in interaction with the Russian peacekeeping force."

Since last year tensions have risen over the Lachin corridor, with Russia focused on its offensive in Ukraine. In December, Azerbaijani activists blocked the Lachin corridor to protest illegal mining. Azerbaijan built the checkpoint following the "threats and provocations" from Armenia. Yerevan has been using the corridor to rotate army staff, "the transfer of weapons and ammunition, the entrance of terrorists, as well as illicit trafficking of natural resources and cultural property." Azerbaijan recorded military convoys entering its territory and "the construction of military infrastructure ... at the point closest to the territory of Azerbaijan."

Yerevan, which relies on Russia as a security guarantor, has grown frustrated over what it sees as Kremlin's failure to fulfill its peacekeeping role.

Relations between the former Soviet republics of Armenia and Azerbaijan have been tense since 1991 when the Armenian military illegally occupied Karabakh, a territory internationally recognized as part of Azerbaijan, and seven adjacent regions for three decades. Clashes erupted on Sept. 27, 2020, with the Armenian Army attacking civilians and Azerbaijani forces, violating several humanitarian cease-fire agreements. During the 44-day conflict, Azerbaijan liberated several cities and around 300 settlements and villages that Armenia had occupied for almost 30 years. The fighting ended with a Russian-brokered agreement on Nov. 10, 2020, which was seen as a victory for Azerbaijan and a defeat for Armenia. However, the cease-fire has been violated several times since then. Several service members from both sides have been killed in clashes recently.

On Saturday, Miller said in a separate statement that Blinken spoke with Pashinian. "Secretary Blinken reiterated that direct dialogue and diplomacy are the only paths to a durable peace in the South Caucasus," the statement said. "He appreciated the Prime Minister's continued commitment to the peace process."

Armenian Foreign Minister Ararat Mirzoyan was set to arrive in Washington, D.C. on Sunday for a working visit as the next round of discussions on the agreement on normalization of relations between Yerevan and Baku is scheduled, Ani Badalyan, a spokesperson for Armenia's Foreign Ministry, said Saturday.