The United Nations and Russia joined calls for a halt in fighting in the Nagorno-Karabakh region where Azerbaijan launched an offensive against Armenian positions.
U.N. Secretary-General Antonio Guterres called for an immediate end to the fighting and for all parties to focus on efforts to bring long-term peace to the region, his spokesman said in a statement.
Russia's foreign ministry on Wednesday urged the sides to "stop hostilities and eliminate civilian casualties."
The U.S. State Department said Secretary of State Antony Blinken spoke by telephone Tuesday with Azerbaijani President Ilham Aliyev and Armenian Prime Minister Nikol Pashinyan.
Blinken told Aliyev there is no military solution and that Azerbaijan and ethnic Armenians in Nagorno-Karabakh "must resume dialogue to resolve outstanding differences."
In his call with Pashinyan, Blinken said the United States "fully supports Armenia's sovereignty, independence, and territorial integrity," the State Department said.
Separatists said 27 people were killed and more than 200 wounded after Azerbaijan began its operation Tuesday.
Azerbaijan said it is conducting an "anti-terrorist operation" in response to landmine explosions that killed four soldiers and two civilians in the region.
The U.N. Security Council is due to hold an emergency meeting on the situation Thursday.
The Nagorno-Karabakh region is entirely within Azerbaijan but is populated largely by ethnic Armenians and had been under ethnic Armenian control since 1994. Parts of it were reclaimed by Azerbaijan after the war in 2020. Russian peacekeepers were placed in the region.
Some information for this story provided by the Associated Press, Agence France-Presse and Reuters