A Hizbullah official in south Lebanon said the party was on full alert in case of any Israeli attack in light of the aggression on the Gaza Strip, but denied fighters were policing the border to prevent attacks on the Jewish state.

"This is a job for the (Lebanese) army and United Nations peacekeepers, not Hizbullah," the official told the Associated Press.

Two cameramen from Hamas-owned Al-Aqsa TV were among six people killed in Israeli air raids on the Gaza Strip, raising Tuesday's death toll to 20, a Hamas spokesman said.

Health officials said a total of more than 125 people had been killed and over 1,000 wounded since Israel began its relentless bombing campaign on November 14 in a bid to stamp out cross-border rocket fire by militants.

Israeli Prime Minister Benjamin Netanyahu told Gaza's Hamas leaders to choose between peace and "the sword" on Tuesday as a diplomatic push intensified to end a week of violence in and around the strip.

"Our hand is outstretched in peace to those of our neighbors who want to make peace with us," Netanyahu said in a statement.

Israel will "pay a heavy price" if it launches a ground operation in the Gaza Strip, Hamas's top military commander warned in a rare audio message broadcast on Tuesday.

"The enemy will pay a heavy price if it thinks of entering Gaza," Mohammed Deif said in the audio message carried by Hamas television station Al-Aqsa.

Turkish Prime Minister Recep Tayyip Erdogan on Tuesday accused Israel of "ethnic cleansing" in Gaza, saying the Jewish state's air raids could not be considered self defense.

"Israel is committing ethnic cleansing by ignoring peace in this region and violating international law," Erdogan said. "It is occupying the Palestinian territory step by step."

Israel is solely responsible for the conflict in Gaza and should be tried for "war crimes," Iran said on Tuesday while stressing that the Palestinians must be "armed to defend" themselves.

"Neither Iran nor Hamas seek conflict or war, or aim to endanger the lives of innocent people," foreign ministry spokesman Ramin Mehmanparast said in his weekly briefing.

Foreign Minister Adnan Mansour traveled to Cairo on Tuesday ahead of heading to the Gaza Strip as part of an Arab ministerial delegation aimed at protesting the Israeli assault against it.

He said from the airport ahead of leaving for Egypt: “Israeli threats do not intimidate Lebanon.”

China backed calls Tuesday for an immediate ceasefire in the Gaza conflict and urged the U.N. Security Council and the international community to bring peace to the region.

A statement by China's Foreign Ministry came as senior Israeli ministers decided overnight to hold off from launching a ground invasion of the Gaza Strip to give Egyptian-led truce efforts a chance to work.

Secretary of State Hillary Clinton will leave Asia on Tuesday to visit Israel, Egypt and Ramallah, stepping up U.S. efforts to avoid a worsening of the Gaza crisis, an official said.

Clinton will meet Israeli Prime Minister Benjamin Netanyahu and discuss the crisis with Egyptian and Palestinian leaders, after leaving President Barack Obama's trip to Southeast Asia, said senior Obama aide Ben Rhodes.

At least 20 Palestinians were killed on Tuesday as Israeli air strikes rocked the Gaza Strip, medics in the Hamas-ruled territory said, as a rocket fired by Palestinian militants exploded near Jerusalem.

Two cameramen from Hamas-owned Al-Aqsa TV were among six people killed in a series of Israeli air raids on Gaza City and the north, a Hamas spokesman said.