WASHINGTON, May 28 (Xinhua) -- U.S. President Donald Trump claimed on Tuesday that Canada would need to pay 61 billion U.S. dollars to join his proposed "Golden Dome" missile defense system.

"I told Canada, which very much wants to be part of our fabulous Golden Dome System, that it will cost $61 Billion Dollars if they remain a separate, but unequal, Nation, but will cost ZERO DOLLARS if they become our cherished 51st State," Trump wrote on Truth Social post.

Trump announced Tuesday the 175 billion U.S. dollar missile shield project, appointing U.S. Space Force General Michael Guetlein to lead what Trump described as a "Manhattan Project-scale" initiative.

The system is designed to create a comprehensive network of satellites capable of detecting, tracking, and intercepting incoming missiles. The project represents a substantial evolution from what was initially announced as the "Iron Dome for America" in the Trump administration's first week, before being renamed "Golden Dome" by the Pentagon in February.

Trump's post comes on the same day as the throne speech was delivered in Canada's Parliament by King Charles III, the head of state for both Canada and the United Kingdom, "during which he asserted Canada's sovereignty and Prime Minister Mark Carney committed his government to joining a major European defence rearmament plan," reported Canadian Broadcasting Corporation on Tuesday.

Carney told the broadcasting network's Power & Politics program in an interview following the speech that he hopes Canada will be able to join ReArm Europe by July 1, a step aimed at reducing the country's dependence on the United States for weapons and munitions, according to the report.

Trump has repeatedly threatened Canadian sovereignty, expressing a desire to annex Canada and turn it into the 51st U.S. state. Carney told Trump earlier this month during an Oval Office meeting that Canada is "not for sale."