Israeli Prime Minister Ariel Sharon headed to the US on Sunday facing a rare dispute with US President George W. Bush over the construction of a "separation fence" in the West Bank.
Sharon, who meets Bush at the White House on Tuesday, flew to Washington after his cabinet agreed to free 540 Palestinian prisoners in a bid to support Palestinian Prime Minister Mahmoud Abbas and the US-backed "road map" to peace.
A senior official travelling with Sharon, whose plane made a brief refuelling stop at an air base in England, said the prisoner release "should happen in the coming week." Officials would meet in the next few days to finalize the list, he said.
Sharon has a hard act to follow -- a landmark visit to the White House on Friday by Abbas that cemented the new Palestinian leader's standing in Washington as a moderate intent on ending nearly three years of violence with Israel.
Hours before Sharon's plane took off for the US capital, an Israeli government spokesman said Israel would continue building the West Bank barrier it says it needs to stop Palestinian suicide bombers from reaching its cities.
At the heart of the dispute over the fence -- a concrete wall in some places and a wire mesh with electronic sensors in others -- are plans to have it cut deep into the West Bank and loop around several Jewish settlements. Those plans have yet to be finalized.
Calling the fence "a problem," Bush said after meeting Abbas, "It is very difficult to develop confidence between the Palestinians and Israel with a wall snaking through the West Bank."
A senior official accompanying Sharon to Washington declined to say what the Israeli leader would tell Bush about the West Bank fence at their talks on Tuesday.
But the official recalled that Sharon told Bush during a summit with Abbas in Jordan in June that the barrier was "not a political border but a security fence."
Palestinians condemn such plans as a land grab.
Sharon could seek to defuse the dispute with Bush over the issue by postponing construction of segments of the barrier that bulge sharply into the central West Bank.
He will arrive at the White House on his eighth visit since taking office carrying a package of confidence-building measures that Israel announced just hours before Bush and Abbas met.
They include the prisoner release, troop withdrawals and issuing more permits allowing Palestinians to enter Israel to work.