Jane Kennedy is to leave the Northern Ireland Office in the cabinet reshuffle caused by the resignation of British Immigrations Minister Beverley Hughes.
Ms Hughes quit amid claims that she knew about an alleged visa scam and was replaced by Works and Pensions Minister Des Browne, who formerly served at the NIO.
Westminster sources said Ms Kennedy would go to the Department of Works and Pensions.
Brent North MP Barry Gardiner was being tipped to the Northern Ireland Office.