Mr Sharon blames the Palestinian leadership

In a separate incident, Israeli army radio said at least four people were injured when a car bomb exploded in the Israeli town of Or Yehuda, south-east of Tel Aviv.

The latest incidents follow an explosion on Sunday, when a Palestinian suicide bomber blew himself up near a bus in a suburb of Tel Aviv, killing one Israeli and wounding more than 40 others.

Clarification sought

Mr Peres is due to hold two days of talks with the Bush administration beginning 4 May.

During his meetings with Colin Powell and the National Security Adviser, Condoleeza Rice, Mr Peres is expected to seek a clarification of the American position, following recent US criticism of Israel's actions, as well as explaining his own country's policy.

For the moment, the American approach is to concentrate on bringing the Israelis and Palestinians together for security talks in the hope that this will lower the level of violence and eventually lay a foundation for renewed peace talks.

But BBC Jerusalem correspondent Hillary Andersson says the violence has almost acquired its own momentum, and with each killing and bombing the emotions are entrenched on both sides.

Army 'opened fire'

Witnesses said hundreds of mourners were marching in an orderly fashion in the funeral near Khan Younis when a traditional mourning volley of gunfire was released. Israeli troops then opened fire from an army post about 500m away.

The 12-year-old boy was shot in the head and died.

The shooting coincided with another bomb explosion - the fourth since Saturday.

Militant Palestinians have said they carried out these bombings.

In a statement to Reuters news agency, the military wing of Hamas vowed to continue the seven-month old Palestinian uprising against the Israeli forces.

Hamas said that Sunday's suicide bomber was the fourth in a list of 10 people prepared to sacrifice their lives.

Israeli Prime Minister Ariel Sharon has blamed the Palestinian Authority for the suicide attack, a charge it denies.

He accuses the Palestinians of not honouring an agreement to stop such attacks.

Palestinian officials deny this, accusing Israel of flagrant violations of the Oslo peace accords - including sending troops and tanks into Palestinian-controlled territories last week.

But, even as the violence continues, a spokesman for Mr Sharon has said Israel has not rejected a joint Jordanian-Egyptian peace initiative, although he has serious reservations about it.

The plan - which has been accepted by the Palestinians - would see both sides committing themselves to stop the cycle of violence as peace talks were restarted.