Prime Minister Stephen Harper is losing a member of his Conservative caucus after Calgary MP Lee Richardson announced Wednesday he is stepping down.

The MP for Calgary Centre announced after question period that he is taking a job as Alberta Premier Alison Redford's principal secretary.

Richardson, 64, was first elected in 1988 as the MP for Calgary Southeast and served until 1993. He was then elected again in 2004 as the MP for Calgary Centre.

He told his fellow MPs during his statement that serving in the House of Commons has been "the greatest honour of my life."

He thanked Harper and former prime minister Brian Mulroney whom he served under during his first stint as a member of Parliament and praised them for their leadership skills.

Richardson also noted that he worked for former prime minister John Diefenbaker on Parliament Hill more than 40 years ago as his executive assistant. He recalled how partisan Diefenbaker was but said he was "a master of this House."

"If I could share one thought with colleagues it would be this: while we advocate for different ideas of Canada, we are all Canadians and we all love our country," an emotional Richardon said.

Richardson bid MPs on all sides of the House farewell and said he hopes to see them at this summer's Calgary Stampede.

NDP House leader Nathan Cullen thanked Richardson for the invitation and wished him the best on behalf of New Democrats.

Interim Liberal leader Bob Rae told Richardson that it has been a privilege to work with him.

"I can't think of anybody more qualified not only to serve [Redford], to serve the people of Alberta but to serve the people of Canada and we wish him well," said Rae.

This won't be Richardson's first experience working for an Alberta premier, he was once chief of staff to Peter Lougheed in the early 1980s.

Bloc Quebecois MP Louis Plamondon and Green MP Elizabeth May also offered their thanks to Richardson for his work in Parliament.

Harper released a statement thanking Richardson for his hard work and dedication.

 "Lee has been a strong advocate for Alberta and a valued voice within our caucus," he said.

"A proud Calgarian, Lee's commitment to his city has been clearly demonstrated through his work with the Calgary Stampede, Calgary Homeless Foundation and other charitable groups," the statement read. 

Harper said on behalf of his wife Laureen, whom Richardson also singled out for thanks during his speech, and his colleagues, he wanted to extend his personal best wishes.