Iraq said formally on Monday that it could no longer guarantee the safety of staff from the US and the UK because of "popular anger" in the wake of the December bombings.

UN legal counsel Hans Corell informed Iraq on Tuesday, however, that the UN was "not in a position to accede to the request to replace the personnel in question on grounds of their nationality".

In a letter faxed to Baghdad, Mr Corell noted that its charter bars UN staff from receiving orders from any government, and said that it was up to UN chief Kofi Annan to make staff decisions.

"It is for the secretary-general of the United Nations ... to determine in the light of all the available information ... which personnel should be assigned to provide humanitarian assistance to Iraq," the UN insisted.

Iraq responsible for safety

Earlier, British diplomat Stuart Eldon said that the UN Secretariat would tell Baghdad that the 14 workers affected must be allowed to stay.

He said the UN would "make it clear that it was for the United Nations to determine who works for its programme in Iraq, not Iraq, and it will underline the responsibility for safeguarding the security of all UN personnel."

US envoy Nancy Soderberg said: "We are pleased that the secretariat has decided not to accede to the latest Iraqi effort to undermine the efforts of the humanitarian workers there to discriminate against some nationalities."