Russian President Dmitry Medvedev discussed the situation in the Gaza Strip with Palestinian President Mahmoud Abbas on Monday, with both leaders stressing the need for an immediate ceasefire, the Kremlin said.

Abbas, who initiated the telephone conversation, thanked Medvedev for the humanitarian aid Russia has delivered so far, and the Russian president vowed that the assistance would continue.

Medvedev ordered on Monday Foreign Minister Sergei Lavrov and Emergency Situations Minister Sergei Shojgu to urgently work on getting more humanitarian aid to Palestinians, the press service said.

Russia sent some 60 tons of humanitarian aid, including foodstuffs, medicine, bedding and tents, to the Gaza Strip on Saturday.

The Israeli military began on Monday a new stage of its ground operation in Gaza, working to clear the Palestinian region of insurgents and terrorist infrastructure, Israeli media reported.

So far, 534 Palestinians have been killed and at least 2,500 injured in the Israeli assault, which became a ground offensive on Saturday after a week of airstrikes. One Israeli soldier has been killed and four civilians died as a result of Palestinian rockets fired in response to the Israeli bombing.

Alexander Saltanov, deputy foreign minister and presidential envoy, met with Israeli Foreign Minister Tzipi Livni on Sunday to try and prevent a humanitarian catastrophe in the region which is home to some 1.5 million Palestinians.

"The central topic under discussion was the sharp worsening of the situation in Gaza and its surroundings. There was a comprehensive exchange of views on possible approaches to overcoming the current crisis. Special focus was paid to the grave humanitarian crisis in the region," Russia''s Foreign Ministry said in a statement.