Prime Minister Paul Martin's trade talk in Asia continued to be sidetracked by his tough-talk defence of the government's same-sex marriage plans.

On Friday, Martin sounded ready to go to the polls over the issue of same-sex marriage.

But in Hong Kong on Saturday evening, Martin backed off that stance somewhat, saying Canadians will not necessarily be heading to the polls if the House of Commons votes against the Liberal government's same-sex marriage bill.

Instead, he said Conservative efforts to rescind same-sex marriage rights already established by the court would cause a vote of confidence, which could result in a vote.

"I will not allow the rights of Canadians to be taken away and I will make that -- the use of the notwithstanding clause -- a motion of confidence," Martin said.

On Friday, Martin said from Beijing: "If you're asking me am I ready to go into an election to uphold the Charter of Rights against those who would attack it, the answer is certainly yes."

Martin's reaction came after Conservative Party leader Stephen Harper said the same-sex bill would eventually lead to the legalization of polygamy.

That notion was rejected as ridiculous by Martin.

But Martin's strong response was met with surprise and criticism even from within his own party -- many of whom are opposed to same-sex marriage themselves.

The Canadian Press reported Liberal backbencher Paul Szabo as saying that an election on the issue would be "irresponsible."

And Liberal MP Pat O'Brien said Martin would be "rolling the dice, big time."

The Liberals have promised a free vote, which means that MPs are free to vote their conscience on the proposed bill.

Speaking in Vancouver on Saturday, Harper said he will try to get the government's proposed legislation amended so that marriage is again restricted to a man and a woman.

Martin said: "The only way that that option can be realized is if in fact you use the not-withstanding clause. Stephen Harper has to come clean. He's got to tell Canadians the truth.

Harper replied: "We have many instances of courts ruling against lower-court rulings against federal statutes and the federal government introducing new legislation without the not-withstanding clause. There's nothing here that's unique about that."

Numerous legal experts have said the only way a law that upholds the traditional definition of marriage can pass constitutional muster is if it uses the not-withstanding clause.

The traditional definition has been found to violate the equality rights of gays and lesbians in six provinces and one territory.

Martin's trip wraps up Sunday when he flies back from Hong Kong.

Martin's trip was an attempt to renew trade ties in Asia, CTV's Joy Malbon reported from Hong Kong.

"They're renewing ties, and that's part of this trade mission - to try and get Canada a toe hold into these Asian markets: India, China, Hong Kong," Malbon reported.

"Basically he's renewing old friendships and re-energizing the relationship."

Martin's Hong Kong agenda includes meeting with Tung Chee Hwa, the Beijing-appointed chief executive of Hong Kong.

He will also visit Sai Wan Military Cemetery to honour Canadian veterans who died in the doomed battle for Hong Kong against Japan in December 1941.

With a report from CTV's Joy Malbon and files from The Canadian Press