Ontario Liberal MP John McCallum has been tapped to take over the reins of his party as interim leader if Stephane Dion steps down as expected on Monday, CTV News has learned.

"People in the Liberal Party are still telling us Dion intends to quit Monday afternoon," CTV's chief political correspondent Craig Oliver said Saturday.

Dion's office released a media alert on Friday announcing Monday's 2 p.m. press conference.

Dion has not spoken publicly since losing his bid to become prime minister in Tuesday's election.

Oliver said that McCallum was chosen because he is bilingual, an authority on finance and well-regarded by the Liberal caucus.

"He's thought of as a consensual interim leader, he's not going to be flying off on his own making decisions that they can't support," Oliver said.

The Liberals have a convention in May, which may be used for a leadership convention.

If Dion stays on he would face a leadership review, which it is believed he would not pass.

Numerous Liberals, on and off the record, have signalled they want Dion out after Tuesday's disastrous election results.

The Liberals are in debt and are looking to rebuild after watching their popular vote numbers drop to near-historic lows for the party.

McCallum was first elected in Markham riding just above northeast Toronto in 2000. He has won re-election in the redistributed Markham-Unionville riding three times since. In Tuesday's general election, McCallum captured 54.9 per cent of the vote.

Before he entered politics, McCallum had been a senior vice-president and chief economist for the Royal Bank of Canada. In office, he had held several portfolios including national revenue and defence.