Montreal - Brian Mulroney has made his first public comments about a high-profile rift that emerged in the Conservative party -- and he's urging party unity.

In an interview with The Canadian Press, the former prime minister said Conservatives needed to put recent differences aside and stick together.

"Obviously it's in the interests of all Conservatives -- Progressive Conservatives and the latter-day group -- to come together in support of common principles," Mulroney said Wednesday.

Mulroney was the central player in a dispute that erupted this spring between party prass and his supporters, who felt he had been treated shabbily by the party. Now Mulroney hopes a party in his honour will help heal the wounds.

A group of friends, including Quebec Premier Jean Charest and some federal MPs, will next month celebrate the 25th anniversary of Mulroney's first landslide election win.

Mulroney says he's looking forward to the fete.

"This is an evening of friendship, so everybody's welcome. I even expect to meet some of my old Liberal friends there," he said.

When asked whether Prime Minister Stephen Harper would attend the Montreal gathering, Mulroney replied: "I have no idea what his plans are."

He said he understood prime ministers had busy schedules, and declined to discuss the personal chill between him and Harper.

Harper issued an arms-length policy on Mulroney while his dealings with lobbyist Karlheinz Schreiber were under investigation.

After that senior members of Harper's team spread the word that Mulroney no longer had a valid party membership card, and therefore no longer a Conservative member.

That gesture infuriated the former prime minister and his allies. Some of them responded by eagerly leaking details to the press about private party discussions.

Mulroney had not commented publicly on the spat.

Although, during his testimony before an inquiry into his business dealings, he took some veiled shots at Harper.

Those barbs included an allusion to the Tories' poor election performance in Quebec last year, which likely cost them a majority government.

Mulroney's allies have suggested that Harper could have won a majority, had he not alienated the former prime minister and his network of Red Tory allies in the province like Charest.

In his interview with The Canadian Press, Mulroney stressed again how successful his organization had been in Quebec.

"When I became the leader (in 1983) we had one seat in Quebec. We had taken, in the election before, 12.9 per cent of the vote," Mulroney said.

"In our first election in '84 we got 58 seats -- and 50 per cent of the popular vote. Then in '88 we got 63 seats out of 74 here -- and I think it was 50-odd per cent of the popular vote.

"So we had quite a following here. And we always had a great organization, a great party, while we were here. And we were able to do some things that people remember favourably."