"We are conscious that we have an ability, if we so choose, to complete the Golden Dome with investments in partnership (with the US). And it's something that we are looking at and something that has been discussed at a high level," he told a news conference.

Trump wants a system that can defend against a wide array of enemy weapons -- from intercontinental ballistic missiles to hypersonic and cruise missiles and drones -- asking for it to be ready in about three years, near the end of his second term in office.

But it faces significant technical and political challenges.

Carney warned of new and increasing missile threats "that in the not too distant future could come from space."

"We take those threats seriously," he said.

Canada and the United States are partners in continental defense through the North American Aerospace Defense Command (NORAD).

At the same time, Ottawa is looking to diversify its trade and security partnerships after once strong Canada-US ties have frayed.

It recently announced a review of a major purchase of US-made F-35 combat planes and signed a deal with Australia to develop Arctic radar systems.

Carney said his government is also in talks with European allies on "becoming a full partner of ReArm Europe," an initiative to bolster European defense capabilities and industry.