Former prime minister Jean Chretien is warning Liberals that the Conservatives and Prime Minister Stephen Harper have a hidden agenda to move Canada further to the right on contentious issues such as abortion and gay marriage.

In a fundraising letter sent out by the Liberal party, Chretien warned that the Conservatives have already "ended gun control and Kyoto" and said they are likely to push their agenda even further.

"Next may be a woman's right to choose, or gay marriage. Then might come capital punishment. And one by one, the values we cherish as Canadians will be gone," Chretien wrote in a letter emailed Monday night.

Harper has publicly said in recent years he has no interest in re-opening the contentious debates around abortion or same-sex marriage.

Still, Chretien urged supporters of the third-place Liberals to take urgent action to protect the party's remaining values.

"Unless we are bold. Unless we seize the moment. Everything we built will start being chipped away," Chretien wrote.

Chretien began the letter, which had a similar tone to a campaign speech, by reviewing his accomplishments during his years in Ottawa.

He pointed out that when he was first elected in 1963 there was no Medicare, Canada Pension Plan, Canadian flag or Charter of Rights.

"The Constitution was British law and there was no Clarity Act. Liberals built these things -- and more," the letter states, adding that a Liberal government also eliminated the deficit and paid down the debt.

The message comes as the Conservatives struggle to stick to their goal to balance the budget by 2014 amid the threat of another global recession.

Chretien also said bluntly that a Conservative government would have sent Canadian troops to Iraq during the U.S. invasion -- something he refused to do as prime minister.

Chretien's ended his letter by calling on supporters to join the Million Conversations Campaign by pledging $5 to start a conversation on a topic of their choice.

He said the campaign has raised enough to start 808,215 conversations, but that the goal was one million.

"And that means, with less than 12 hours left, you must decide if your values are worth fighting for. It's now or never," Chretien said.