Foreign ministers from the United States, Russia and France are urging Azerbaijan and Armenia to take steps to end the conflict over the disputed enclave of Nagorno-Karabakh.

Russian Foreign Minister Sergei Lavrov, U.S. Secretary of State Hillary Clinton and French Foreign Minister Alain Juppe made the call in a statement issued Thursday to mark the 20th anniversary of the formal request to convene a conference on the issue.

The three countries comprise the so-called Minsk Group, an international panel trying to negotiate an end to the conflict.

Thursday's statement calls on both sides to demonstrate the “political will” needed to achieve a lasting and peaceful settlement.

It says people in the region have suffered most from the consequences of war, adding that any delay in reaching a settlement will only prolong their hardships.

Ethnic Armenian separatists in Nagorno-Karabakh, a region deep inside Azerbaijan, declared independence from the Baku government in 1988, triggering a six-year war that claimed 35,000 lives and left more than 1 million people homeless.

Major fighting ended after a 1994 cease-fire, but there are frequent reports of firefights along the border.

Repeated international efforts to broker a peace deal have failed, and border tensions between Armenian-backed forces and Azerbaijani troops remain high.