WASHINGTON, April 4. /TASS/. US Vice-President Joe Biden on Monday said he held talks with Azerbaijani President Ilham Aliyev and Armenian President Serzh Sargsyan and urged them to settle the Nagorno-Karabakh conflict.
"As I told Presidents Aliyev and Sargsyan, comprehensive settlement in Nagorno-Karabakh is critical for their stability, security, prosperity," he wrote in his Twitter microblog.
Tensions in Nagorno-Karabakh soared along the engagement line separating the conflicting parties in the small hours of April 2. Fierce clashes followed. Either side blamed the other for breaching truce.
Neighbouring Armenia and Azerbaijan fell out with each other in the late 1980s because of Nagorno-Karabakh, the disputed territory that had been part of Azerbaijan before the Soviet Union break-up but was mainly populated by Armenians.
In 1991-1994, the confrontation spilled over into large-scale military action for control over the enclave and some adjacent territories. Thousands left their homes on both sides in a conflict that killed 30,000. A truce was called between Armenia and the Nagorno-Karabakh republic on one side and Azerbaijan on the other in May 1994.
Talks on Nagorno-Karabakh have been held on the basis of the so-called Madrid Principles suggested by co-chairs of the Minsk Group of the Organization for Security and Cooperation in Europe (OSCE) - Russia, France and the United States - in December 2007 in the Spanish capital.