United Nations human rights chief Sergio Vieira de Mello has been appointed the world body's special representative in Iraq for four months and will work with the United States and Britain in reconstruction of the country and rebuilding of its devastated institutions.

But de Mello, who has strong backing of the United States, said his appointment is only for four months so that he can hold his current position.

Secretary General Kofi Annan informed the presidents of Security Council and the General Assembly of his choice on Friday, just 24 hours after the Council adopted a resolution lifting sanctions on Iraq. Annan is expected to formally introduce him at press conference on Tuesday. Monday is UN holiday.

Annan said he has selected de Mello because of "his unique experience in serving the UN in post-conflict situations in the past."