Mr Colin Powell is to end his visit to Israel tomorrow and make a stopover in Cairo.
The US Secretary of State said he was making progress but hinted he might not achieve a mutually proclaimed ceasefire.
Mr Powell is expected to meet Israeli Prime Minister Mr Ariel Sharon later today and Palestinian President Mr Yasser Arafat tomorrow before leaving.
His announcement comes as Israeli forces pulled out of the West Bank town of Tulkarm after earlier seizing nine Palestinians and wounding another nine in the town.
The fresh incursion came only hours after Mr Sharon promised limited pullbacks in the West Bank. The move also only came hours after soldiers seized Palestinian leader Mr Marwan Barghouthi (42) - considered to be one of Mr Arafat's potential successors.
Israeli infantry also entered the Askar refugee camp in the northern West Bank city of Nablus to carry out house searches this morning.
Mr Sharon had pledged earlier to pull Israeli forces out from the battered West Bank cities of Nablus and Jenin within a week.
He said his forces would be out of Jenin - which suffered massive destruction in the fiercest fighting of the Israeli offensive - within a "couple of days" and would leave Nablus in "not more than a week".
But he told CNN that troops would stay in Bethlehem until a standoff with gunmen in the Church of Nativity was over. They would also keep Mr Arafat's headquarters under siege until four wanted men said to be inside were handed over.
US President Mr Bush spoke to Mr Sharon by telephone for 15 minutes yesterday and said he saw the Israeli leader's pledge to start a withdrawal as positive, the White House said.
AFP and