Manchester United manager Alex Ferguson, Bob Geldof and Terry Wogan are among the guests due to attend a Fianna Fail dinner hosted by the Taoiseach, Mr Ahern, in London on Friday.
Up to 400 people are expected at the £150-ahead dinner, which will take place in the Grosvenor Park Hotel in the city centre. Prominent members of the London-Irish community are expected to attend along with celebrity guests including actor Stephen Fry and the McGann brothers.