The United Nations is planning to evacuate non-essential foreign staff from the Gaza Strip due to the deteriorating security situation.
A UN official in Jerusalem said a decision was taken to move Gaza to security level "Phase Four" - one step below the maximum "Phase Five", which requires all international staff to leave.
Unrest surged in the Gaza Strip at the weekend. Four French aid workers and two local officials were briefly held hostage by gunmen demanding reforms. At least 18 people were wounded in later clashes.
"Stage Four was declared in New York in consultation with the people on the ground. Non-essential staff are being pulled out today," the official said.
He said many staff were already on summer holidays so only a few would need to be evacuated.
The UN Relief and Works Agency, which cares for Palestinian refugees, said on Tuesday it was pulling out 20 staff who regularly have to cross into Israel. It said it feared they could be caught in crossfire near the border.
Meanwhile the European Union's top diplomat today raised pressure on Palestinian President Yasser Arafat by hinting the EU would reconsider relations with him if his prime minister quit in a leadership struggle.
The EU has been the biggest donor to the Palestinian Authority since Palestinians won self-rule in Israeli-occupied lands in 1994 but has grown exasperated with Mr Arafat's resistance to reforms seen as crucial to any future Middle East peace.
Mr Solana said after talks with Israel's foreign minister the EU wanted a Palestinian prime minister "empowered" to carry out reforms to purge high-level corruption and stop a spiral into anarchy. Mr Arafat's inaction has stirred Palestinian unrest.
Asked about the possible departure of Palestinian Prime Minister Ahmed Qurie, frustrated at Arafat's refusal to cede control over lawless security services, Mr Solana told reporters: "If that happens we will have to rethink a lot of things."
Mr Solana, pressed as to whether he was referring to Mr Arafat in his remark, told reporters: "That, and a lot of things." An EU official said later Mr Solana could also have been talking about the Palestinian Authority in broader terms.
His call for an "empowered" premier, echoing one he made earlier in the week, was a veiled slap at the Palestinian president who had long enjoyed strong support within Europe.
EU leaders have continued contact with Mr Arafat since a Palestinian revolt broke out in 2000 after the collapse of statehood talks, but many have cooled toward the ex-guerrilla leader over burgeoning corruption and chaos under his rule.