Canada will not put any money into building the missile shield and it will not allow Washington to station rockets on Canadian soil as the price of participation in the multibillion-dollar program, Mr. Martin told Global National in a year-end interview.

Touching on another issue that could cause friction with Mr. Bush, Mr. Martin said Canada was prepared to accept U.S. citizens who do not want to serve in the war in Iraq.

"In terms of immigration, we are a country of immigrants and we will take immigrants from around the world. I'm not going to discriminate," he said.

When asked whether the prime minister was referring to ongoing attempts by Jeremy Hinzman, a 26-year-old U.S. deserter, to gain asylum in Canada after refusing to serve in what he calls "an illegal war," Martin spokesman Scott Reid said the prime minister "was not commenting on any individual case and certainly was not sending a signal to the immigration board."

Mr. Martin was emphatic Canada's participation in the missile defence program would depend on a key decision-making role in the U.S. command and control structure that operates the shield.

"The decision as to whether or not we participate in the ballistic missile defence system is going to depend on whether, in fact, Canada can have a voice in the structure," Mr. Martin said in the interview, to be broadcast Christmas Day.

"I'm not going to put money into it. I'm going to put money into our priorities ... Having missiles on our territory is not one of those priorities."

The conditions laid out by Mr. Martin are the clearest indication to date the Liberal government is increasingly disinterested in the missile defence program despite Mr. Bush's public appeal during his visit to Canada earlier this month.

Mr. Martin has been under heavy pressure from the Liberal caucus and the party's grassroots to reject the defence shield, which he admitted may not even work to knock down incoming missiles from rogue states or global terrorists.

"Do I believe it could work tomorrow? I suspect there are very few people out there who testify that it could. Do I believe eventually technology could bring it to that point, in all likelihood, but I'm not a rocket expert," he said in another TV interview.

Mr. Martin said Canada is not even close to negotiating a memorandum of understanding with the U.S. on missile defence, but added any document must include guarantees that it would not lead to the weaponization of space.

Canada would immediately pull out of the defence shield if it were to join and the U.S. subsequently put missile weapon systems in space.

"I don't believe space belongs to any country," Mr. Martin said.

"We will not engage in the weaponization of space."

He acknowledged for the first time that next year's budget will pump money into Canada's hard-pressed military, including funds to allow the Armed Forces to recruit 5,000 more troops over the next five years.

Mr. Martin admitted he struggled over his personal belief in the traditional marriage, but finally decided same-sex weddings were a right entitled to all citizens regardless of their sexual orientation.

He defended his decision to force cabinet to vote in favour of same-sex even though eight ministers oppose the concept and some may break rank.

Mr. Martin said he was confident cabinet would stick together, although Northern Affairs Minister Joe Comuzzi has indicated he might vote against the legislation and Natural Resources Minister John Efford said he may resign his post over the same-sex marriage issue.

"I don't believe that that is going to be the case" Mr. Martin said.

"Are there members of the cabinet who are struggling with it the way I did, yes. I believe ultimately that this is a charter right and I think that view is the one that will prevail."

Mr. Martin appeared confident throughout a series of TV interviews in which he was repeatedly asked why he has been dubbed a ditherer who can't easily make decisions.

He conceded that at the beginning of his reign, he got involved in too many files and failed to focus in on key issues, but said he is now "hitting his stride" and his government has been the most active Parliament since 1974. He strongly defended his record in achieving a health accord and promised action in the new year on a national child-care program.

Robert fife is parliamentary bureau chief