UNITED NATIONS, Oct 7: The unions representing over 60,000 United Nations workers called on Secretary General Kofi Annan on Wednesday to withdraw all UN staff from Iraq because of "unprecedented" risk to their safety and security.

In a joint letter to Mr Annan, the unions cited a dramatic escalation in attacks in Iraq and said the UN regrettably "has become a direct target, one that is particularly prone to attacks by ruthless extremist terrorist factions."

"Just one staff member is one staff member too many in Iraq," they said. "We ... appeal to your good judgment to ensure that no further staff members be sent to Iraq and that those already deployed be instructed to leave as soon as possible."

Robert Weisell, president of the Federation of International Civil Servants' Associations, said he understood "the extreme political pressures calling for the presence (and an increased one at that) of the UN in Iraq."