The US envoy to the Northern Ireland peace process, Mr Richard Haass, is leaving the Bush administration to become president of the New York-based Council on Foreign Relations from July 1st.
Mr Haass, who is director of policy planning at the State Department, may not, however, immediately relinquish his role as US intermediary in the Northern Ireland peace process.
The question has not been decided but "is being worked on right now", an official in Mr Haass's office told The Irish Times yesterday.
Sources in Washington said Mr Haass was willing to consider extending his role as special representative to the peace process.
Such a decision would have to be approved by US Secretary of State, Mr Colin Powell, and signed off by President Bush, both of whom are returning to the US from a lengthy trip abroad.
During his time on Northern Ireland, Mr Haass has earned enormous respect from all sides for his expertise and his good relationships with the parties, and it is likely that there will be considerable pressure from Irish American Congress members for his retention in some capacity.
He was recently in Ireland for consultations on the possibility of holding new elections to a Northern Ireland Assembly in the autumn.
Mr Haass has a reputation as a multilateralist and is reported to have experienced some frustrations with Bush administration policies. He denied he was leaving over policy differences, though he told the New York Times: "Of course I've had my share of battles."
He said the reason he was leaving was that "this offer came along and the opportunity to lead an organisation with tremendous influence is not something anyone would lightly pass up".
His responsibilities on Northern Ireland included long-term planning and providing independent advice to Mr Powell.
State Department officials said they were not aware of any decision on a replacement for Mr Haass, who was also special co-ordinator on the future of Afghanistan.
The Council on Foreign Relations announced yesterday that Mr Haass would replace Mr Leslie Gelb, a former State Department and Pentagon official, as president of the think-tank. The council has an endowment of some $140 million and about 4,000 members, many of them leading figures in the foreign policy establishment.
It is dedicated to "increasing America's understanding of the world and contributing ideas to US foreign policy".
Mr Haass was a close adviser to President Bush's father during the first Iraq war in 1991. He served as vice-president of the Brookings Institution before joining the State Department.