Armenia and Azerbaijan once more accused each other of bombing residential areas on Saturday, in defiance of a pact to avoid the deliberate targeting of civilians in and around the disputed Nagorno-Karabakh region.

Shelling was reported by both sides within hours of the latest agreement to defuse the conflict, reached after talks in Geneva between the two countries' foreign ministers and envoys from France, Russia and the United States.

The agreement fell short of what would have been a fourth ceasefire since fighting began on September 27. The death toll in the worst fighting in the South Caucasus for more than 25 years has surpassed 1,000 and is possibly much higher.

The central market in Stepanakert, the largest city in the disputed region, had reportedly come under fire and that large parts of it had been burned.

Armenia's defense ministry said several civilians had been wounded in attacks on the city of Shushi, 15 kilometers (nine miles) to the south. And a civilian in Martuni region in Nagorno-Karabakh was reported to die when a shell hit his home.

Azerbaijan's defense ministry denied these accusations. It said that the regions of Terter, Aghdam and Aghjabedi had come under artillery fire, as had Gubadli, a town between the enclave and the Iranian border that was taken by Azeri troops this week.

In response to a request by Armenian Prime Minister Nikol Pashinyan to outline the extent of Moscow's support, Russia's Foreign Ministry said it would provide "all assistance required" should the conflict spill onto "the territory of Armenia" – land that is outside the current conflict zone.

Despite repeated international attempts to secure a ceasefire, fighting between the two sides has intensified in recent days. Russia has estimated as many as 5,000 deaths on both sides.

(With input from Reuters)