A who's who of Canada's conservative movement, past and present, is converging at a 25th anniversary celebration of Brian Mulroney's massive 1984 electoral win.

The former prime minister, his wife Mila, and four children are on hand at a downtown Montreal hotel to greet members of the former Tory government.

Among the veteran politicians in the crowd are former Mulroney cabinet ministers such as Joe Clark, Michael Wilson, and Elmer MacKay, current Quebec Premier Jean Charest, and former New Brunswick Premier Bernard Lord.

About half the current Conservative cabinet is expected to attend - Finance Minister Jim Flaherty and Defence Minister Peter MacKay to name just a few.

Prime Minister Stephen Harper is expected to deliver a message of congratulations to Mulroney by pre-recorded video, in a gesture of party unity. His wife Laureen is also on the guest list.

Relations between the two men have been strained since Harper called a public inquiry into Mulroney's business dealings with German lobbyist Karlheinz Schreiber and directed his cabinet to cut off contact with him.