A. Blinken discussed peace negotiations with the leaders of Armenia and Azerbaijan

Baku and Yerevan have been in conflict for decades over control of the Nagorno-Karabakh region. Baku forces recaptured control of the enclave from Armenian separatists in a flash in September.

Washington, Brussels and Moscow are making diplomatic efforts to normalize relations between the two countries, but a broader peace agreement has still not been reached.

Azerbaijan refused to take part in the planned talks with the US earlier this month because of what it sees as Washington’s biased position.

During a telephone conversation with Azerbaijani President Ilham Aliyev on Tuesday, Blinken emphasized the United States’ strong relationship with Azerbaijan, but also noted recent concerns, his spokesman Matthew Miller said in a statement.

The conversation was seen as an attempt to bring the United States back to the center of negotiations amid a diplomatic standoff between Washington and Baku.

Earlier in November, US Assistant Secretary of State for European and Eurasian Affairs James O’Brien said that Washington had canceled several high-level visits to Azerbaijan and condemned Baku’s September 19 one-day military operation in Nagorno-Karabakh.

After Azerbaijan regained control of the region, almost all 100 thousand its population, mostly ethnic Armenians, fled to Armenia, causing a refugee crisis in the country.

Nagorno-Karabakh is internationally recognized as part of Azerbaijan, but has been home to an Armenian majority for decades. Since the early 1990s, the region has been controlled by pro-Armenian separatists.

According to Baku, I. Aliyev told A. Blinken that Washington’s recent statements and actions have severely damaged relations between Azerbaijan and the United States.

Nevertheless, according to the Azerbaijani side, both countries agreed that Mr. O’Brien would visit Azerbaijan in December, and Mr. Blinken, in turn, promised to lift the ban on Azerbaijani officials visiting the United States.

In a separate conversation, Blinken also spoke with Armenian Prime Minister Nikol Pashinian and emphasized that the United States supports efforts to reach a lasting and fair peace agreement, his spokesman said.

There has been little progress so far in internationally brokered peace talks between the former Soviet republics, but the leaders of both countries said a comprehensive deal could still be signed by the end of the year.