One Azeri soldier were killed in an exchange of fire near Azerbaijan's breakaway Nagorno-Karabakh region, the region's military said on Saturday.

Four ethnic Armenian troops were also killed in the clashes.

Skirmishes erupt frequently along front lines near Nagorno-Karabakh, a small mountainous region under the control of ethnic Armenians who fought a six-year separatist war with support from neighbouring Armenia.

In Baku, Azerbaijan's Defence Ministry confirmed a clash took place and an Azeri soldier was killed.

An estimated 30,000 people were killed and 1 million displaced before a ceasefire was reached in 1994 but a peace accord has never been agreed and the ethnic Armenian leadership's claim of independence has not been recognised by any country.

A day before Friday's clash, the presidents of Armenia and Azerbaijan met, together with Russian President Dmitry Medvedev, and agreed to continue internationally mediated efforts to resolve the conflict.

The dispute between mostly Muslim Azerbaijan and mostly Christian Armenia remains a threat to stability in the South Caucasus, an important route for oil and gas supplies from the Caspian region to Europe.

Reuters