A Conservative member of parliament from Ontario has defected to the Liberal Party, bringing Canada's prime minister, Mark Carney, inches away from leading a majority in the House of Commons.

Marilyn Gladu announced her switch this week, saying the community she represents wants "serious leadership and a real plan to build a stronger and more independent Canadian economy".

The fifth MP to leave their party in recent months, Gladu has brought a majority government within arm's reach for the Liberals. They now have 171 seats - one shy of the required 172 for a majority.

Canada's Conservative leader, Pierre Poilievre, accused Carney of trying to seize a majority "through dirty backroom deals".

Last month, MP Lori Idlout, who represents Nunavut, left the New Democratic Party to join Carney's caucus.