Deputy Liberal Leader Michael Ignatieff says it's hard to believe the Conservatives when they say Chuck Cadman was planning an election campaign two months before he died of cancer.

In the House of Commons on Monday, Ignatieff disputed the suggestion that the Tories merely offered financial help for the next election and a riding nomination when they met secretly with the Independent MP in May 2005.

"He wasn't going to run," said Ignatieff during question period on Monday. "He didn't need their help. How will they repeat these stories? No one believes them."

The Conservatives, however, stood by their version of events on Monday. They said the only money they offered the ailing MP in the days before a crucial House of Commons budget vote was to finance his next run for office.

"Chuck Cadman was going to run again," MP James Moore, the government's go-to man on the contentious portfolio, said Monday. "There was only one offer -- that he rejoin the Conservative Party."

On May 12, 2005, Cadman told CTV's Canada AM he planned to run again.

The parties have been at loggerheads over what exactly was offered to try to earn Cadman's renewed allegiance. Cadman's wife, daughter and son-in-law have all stated he was offered a $1-million life insurance policy to help bring down the Liberal government.

It could mean the difference between normal campaign financing and a bribe for a vote -- which can carry a penalty of up to 14 years in prison.

Cadman, the member for British Columbia's Surrey North riding, sided with the Liberals during the contentious vote, preventing the fall of the Paul Martin government. If the Liberals had lost, an election would have been called.

"The key issue is what the prime minister meant in 2005 when on tape he said 'There were discussions with Mr. Cadman that involve financial considerations.' What does he mean by those words?" Ignatieff told CTV's Mike Duffy on Monday.

"(It seems like a) financial offer... that involves dealing with people's financial insecurities."

Top Liberals recently became the subject of a legal threat after posting claims about the incident on their website. It marks the first time a sitting Prime Minister has sued the opposition for libel.

Liberal Leader Stephane Dion, the Liberal Party of Canada and MPs Ralph Goodale and Ignatieff have been threatened with a lawsuit and expect the paperwork any day, something Ignatieff says is not in keeping with Canada's democratic traditions.

"In the House of Commons I raise matters that are of legitimate public concern," Ignatieff said. "What do we get? We get sued. Why is the prime minister trying to sue members of Parliament when they're trying to do their job?"