Israeli Prime Minister Ariel Sharon said he will likely delay the Gaza withdrawal, which was scheduled for July 20, by three weeks because of religious reasons.

Many Israelis observe a three week mourning period in the run-up to the religious festival marking the destruction of the second Jewish Temple.

The event, which falls on August 14, commemorates the breaching of the walls of Jerusalem in 70 AD.

“We need to do everything to make the evacuation easier and to allow settlers to overcome the crisis of disengagement. These, effectively, are to be difficult days in the history of the Jewish people,” announced Mr Sharon.

A postponement means the month-long disengagement operation would get underway on August 15.

The delay allows the government more room to plan for the withdrawal, but would also give Jewish extremists more time to organise resistance.

Earlier on Monday, plans were revealed for the construction of 50 new homes at the religious settlement of Elkana in the northern West Bank.

The announcement of the new homes came just days after US President George W. Bush warned Mr Sharon against any expansion of settlements and was swiftly followed by a rebuke from Washington.

“Israel should not expand settlements,” said White House spokesman Scott McClellan of the planned construction work at Elkana. “We will be seeking clarification from the government of Israel.”

“The roadmap has obligations for both parties. Israel should not be expanding settlements, and the Palestinian leaders need to act to dismantle terrorist organisations,” he added.

The move was also denounced by the Palestinians as well as the Israeli anti-settlement watchdog Peace Now, as a clear violation of the government’s commitments under the roadmap.

“While the Israelis talk about leaving 2,100 housing units in the Gaza Strip and northern West Bank, they are at the same time tripling the numbers in other parts of the West Bank and (occupied east) Jerusalem,” Palestinian chief negotiator Saeb Erakat said.

At a summit in Texas last week, Mr Bush told the Israeli prime minister to conform to the roadmap which “clearly says no expansion of settlements”.

Mr Sharon is planning to pull all the 8,000 Jewish settlers out of the Gaza Strip this summer as part of a wider disengagement plan.

In turn, he is hoping to cement Israeli control over areas such as Elkana, where the vast majority of the 245,000 settlers live.