Israel was on the brink of launching a full-scale invasion into Gaza on Sunday, following massive air strikes over the weekend that killed more than 290 Palestinians.

It was the bloodiest weekend for Palestinians in 60 years of conflict and triggered worldwide calls for peace and outpourings of fury within the Arab world.

Hamas leader Ismail Haniyeh claimed that Palistine had never seen an uglier massacre. His Islamist group vowed revenge including suicide bombings in Israel's "cafes and streets".

Despite the build-up of troops on the border, Israeli military commentators said the offensive did not appear to be aimed at retaking the Gaza Strip or destroying the territory's Hamas government, ambitious goals that could prove difficult and politically risky to achieve ahead of Israel's Feb 10 parliamentary election.

Instead, they said Israel wanted to strengthen its deterrence power and force Hamas into a new truce that would lead to a long-term halt to cross-border rocket salvoes.

Thousands rallied in cities in the Arab world to condemn Israel's air raids on Palestinian militants in the Gaza Strip. Major anti-Israeli rallies were held in Egypt, Iraq, Jordan, Lebanon, Sudan, Syria and Yemen.