Mr Sharon told Sunday’s cabinet meeting that he had given the army carte blanche to crush militant groups in Gaza, in reaction to a Palestinian attack at a border crossing on Thursday that killed six Israelis.

A Palestinian man and a woman were killed by Israeli tank fire in the south of the Gaza Strip on Sunday, AFP reported.

During a speech on Saturday after being sworn in as Palestinian Authority President, Mahmoud Abbas called on militants to “bring about the calm needed to enable a credible, serious peace process.”

Soon after, the PLO’s decision-making executive committee demanded that armed factions halt attacks.

“The committee gave its full support to Abu Mazen’s (Abbas’s) inauguration speech to stop all military acts that harm our national interest,” the committee said in a statement after meeting in the West Bank town of Ramallah.

Such attacks merely “give an excuse to the Israeli position which is aimed at sabotaging Palestinian stability and the implementation of the roadmap,” the committee added.

Three militant factions claimed joint responsibility for Thursday’s suicide attack at the Karni border crossing, including the Al-Aqsa Martyrs’ Brigades which is an armed offshoot of Mr Abbas’s own mainstream Fatah movement.

Mr Sharon ordered a freeze on all contacts with the Palestinian Authority on Friday in the aftermath of the attack.

“Israel is severing all planned contacts with the Palestinians on all levels, from security to government leadership,” spokesman Assaf Shariv said.

“Everything is cancelled until they take steps against terror, so we can see there is not only talk but also action. Abbas knows who carried out the attack, so he will be the one to stop them. It’s very easy,” he said.

The head of preventive security meanwhile said that the Palestinian Authority would take no cooercive measures against the militant groups without Israel showing a clear desire to move forward.

Rashid Abu Shbak said the Palestinian Authority would not give Israel “security for free”.

Mr Abbas is due to travel to Gaza City on Wednesday, the stronghold of the radical Islamist movements Hamas and Islamic Jihad, for talks with their leaderships about securing a new ceasefire.