The United States should make more effective use of its clout in the Middle East to bring about the establishment of a Palestinian state, Russia''s foreign minister said on Monday.

Israel continued on Monday airstrikes on suspected militant infrastructure in the Gaza Strip. The extensive attacks, which local medical services say have killed 310 Palestinians, began on Saturday in response to rocket and mortar fire by Palestinian militants on southern Israel.

"Needless to say, if we want changes, these changes can be brought about through more persistent and effective use of U.S. resources in the region, which are still far more substantial than those of other players," Sergei Lavrov said, adding that any agreement reached should be based on international law and UN resolutions on the establishment of a Palestinian state.

He also said there was no alternative to direct negotiations between the Palestinians and Israelis as a key to a comprehensive peace process including Syria and Lebanon.

The foreign minister said a Middle East settlement was impossible without an agreement between the Fatah group of Palestinian President Mahmoud Abbas, which governs the West Bank, and Hamas, the Islamic movement that took control of the Gaza Strip.

Israel earlier announced that the military operation would go on until the population in southern Israel "no longer lives in terror and in fear of constant rocket barrages."

It has mobilized up to 6,500 reservists and deployed tanks on Gaza''s edge in preparation for a possible ground offensive on the coastal enclave of 1.5 million Palestinians.

In response to the Israeli airstrikes, Palestinians have reportedly fired about 150 rockets and mortar bombs at the Jewish state, killing two Israelis.

The International Red Cross said hospitals in the Gaza Strip had been overwhelmed and were unable to cope with the more than 1,400 wounded in the airstrikes.

Meanwhile, the UN Security Council has called for an immediate halt to all military actions in Gaza. The non-binding statement adopted by the 15-member body calls for an immediate halt to all violence and urges the parties to immediately stop all military activity.