Israel is provoking Islamic movements with its baseless, politically motivated military campaign in Gaza, the Palestinian ambassador to Russia said on Wednesday.

"Israel did not have any basis for unleashing this war," Afif Safieh said at a news conference in Moscow. "Israel is provoking the Islamic movements [in Gaza], not vice versa."

He also said the Israeli leadership, in particular Foreign Minister Tzipi Livni and Defense Minister Ehud Barak, had launched the military operation to improve their chances of victory in upcoming elections in Israel.

"Livni and Barak started the war to score political points," he said.

The death toll in Gaza since December 27, when Israel first launched airstrikes on the enclave, is reported to have risen to over 920, with half of the dead civilians, while more than 4,000 have been injured.

Israel bombed southern Gaza earlier on Wednesday aiming to destroy tunnels to Egypt while its troops continued ground operations in the north of the enclave, Palestinian medics and fighters said.

The main focus of the aerial bombardment is the so-called Philadelphia corridor on the Gaza-Egypt border, where Israel wants to destroy tunnels it says are used to smuggle weapons and ammunition to Palestinian militants. Some 200 tunnels are believed to have been destroyed so far.