Moscow (dpa) - Hundreds of civilian homes in the disputed Nagorno-Karabakh region have been destroyed this week during fighting between Azerbaijan and Armenia, the Red Cross said on Friday.

Azerbaijan has launched an offensive to regain control over the disputed territory, held by Christian Armenian separatists but recognized by the United Nations as part of predominantly Muslim Azerbaijan.

The United Nations, the European Union and regional power Russia, a close military ally of Armenia, have all called for an immediate ceasefire. Regional power Turkey has offered all means of assistance to Azerbaijan but has denied direct involvement.

Homes, schools and hospitals have been destroyed by heavy artillery, the International Committee of the Red Cross (ICRC) said in Geneva, citing reports from the ground.

The humanitarian organization did not give an estimate for civilian deaths and injuries, but said that there were casualties among adults and children on both sides of the line of contact, and in Armenia.

"Our ability to move in the field is limited because of the intensity of fighting and the volatility of the situation," said Bertrand Lamon, who heads the ICRC mission in Nagorno-Karabakh.

Armenia said on Friday that it was ready to engage in peace talks via the Organization for Security and Cooperation in Europe (OSCE) as it reported over 50 more of its soldiers killed in the fighting.

"We stand ready to engage with the OSCE Minsk Group co-chair countries to re-establish a ceasefire regime based on the 1994-1995 agreements," Armenia's Foreign Ministry said in a statement.

The fighting, which erupted on Sunday, is an extension of decades-old hostilities over the disputed Nagorno-Karabakh region.

Armenia's Foreign Ministry warned that while it would welcome such peace talks, Azerbaijan's "aggression against Nagorno-Karabakh will continue to receive [Armenia's] strong and resolute response."

Armenian state news agency Armenpress on Friday reported an additional 54 soldiers killed in action, raising the death toll among the Armenian forces to over 150.

Azerbaijan's Foreign Ministry said in a statement that the country has been conducting "counter-offensive measures within its internationally recognized borders in response to the new military aggression of Armenia."

It noted a demand by EU power France for renewed peace talks via the OSCE, following a telephone conversation by France and Azerbaijan's top diplomats.

France earlier this week accused Azerbaijan of initiating the flare-up.

The fighting has been the deadliest since a similar flare-up four years ago.

Azerbaijan appears to be seeking to regain control over two districts in Nagorno-Karabakh's south-east, Fuzuli and Jabrayil, which historically had substantial ethnic Azerbaijani populations.

Azerbaijan and Armenia previously fought a war over Nagorno-Karabakh in the late 1980s and early 1990s as they transitioned into independent countries amid the collapse of the Soviet Union.

The war, which ended with a fragile peace treaty in 1994, is estimated to have claimed the lives of tens of thousands of people, including more than a thousand civilians.