OTTAWA — Defence Minister David McGuinty says that Canada still doesn’t know what it would cost to join U.S. President Donald Trump’s proposed “Golden Dome” missile defence program.

On Tuesday, in a social media post, Trump said it would cost Canada $61 billion to join as a sovereign country but nothing at all if it became a U.S. state.

Trump claimed that Canada is “considering the offer.”

When asked about Trump’s comments, Prime Minister Mark Carney said he won’t negotiate in public.

Trump announced plans for a complex missile defence system modelled after Israel’s “Iron Dome” earlier this month and claimed it would cost $175 billion.

The Congressional Budget Office says that the space-based components alone could cost more than half a trillion dollars over the next 20 years.

— With files from Kelly Malone in Washington.

This report by The Canadian Press was first published May 28, 2025.

David Baxter, The Canadian Press