Armenian and Azerbaijani forces were engaged in fierce clashes yesterday as fighting over the disputed Nagorno-Karabakh region intensified after its main city came under heavy shelling.
The leader of the breakaway province said he was heading to the front and that the "final battle" for the region had begun, seven days after new fighting erupted in the decades-old dispute.
Armenia's defence ministry said Karabakh's separatist forces had repelled a "massive attack" by Azerbaijan in one area of the frontline and had launched a counter-offensive.
"Heavy fighting is ongoing on other flanks," defence ministry spokeswoman Shushan Stepanyan said.
Azerbaijan's defence ministry said its forces had "captured new footholds" and that the Armenians had "suffered serious losses in manpower and military hardware".
Both sides have been accused of hitting civilian areas, with Azerbaijan saying yesterday that Armenian artillery had shelled 19 of its settlements overnight.
The Armenian side has reported 158 military deaths and said 14 civilians have been killed. Azerbaijan has reported 19 civilian deaths but has not confirmed any fatalities among its troops.
Russia, the United States and France -- whose leaders co-chair a mediation group that has failed to bring about a political resolution to the conflict -- called on the warring sides this week to immediately agree a ceasefire.
Karabakh's declaration of independence from Azerbaijan amid the collapse of the Soviet Union sparked a war in the early 1990s that claimed 30,000 lives. Talks to resolve the conflict have made little progress since a 1994 ceasefire agreement.
The breakaway province is not recognised as independent by any country -- including Armenia -- and Karabakh's foreign ministry yesterday said that only receiving official status from world leaders could resolve the military flare-up.
The fighting has threatened to balloon into a regional conflict drawing in powerful players Russia and Turkey. Armenia is in a military alliance of former Soviet countries that is led by Moscow, which maintains a military base there, while Nato member Turkey has signalled its full support for Azerbaijan's military operations.