According to an editorial in the broadsheet The Globe and Mail, Harry and Meghan's decision to step back from royal duties and move to Canada would impinge upon the "Canadian monarchy".
"Our royals don't live here. They reign from a distance," the editorial says.
"A royal living in this country does not accord with the long-standing nature of the relationship between Canada and Britain, and Canada and the Crown.
"This country's unique monarchy, and its delicate yet essential place in our constitutional system, means that a royal resident ... is not something that Canada can allow."
The editorial went on to stress Canada's place in the Commonwealth as an "equal, independent nation" to Britain and urged the Canadian government to deny residence to the Duke and Duchess of Sussex.
"The concept of the Crown is at the centre of the Canadian system of government.
"But though Canada borrowed from Britain, it isn't Britain and never was. And this country long ago took steps to make that unmistakably clear.
"Canada is not a halfway house for anyone looking to get out of Britain while remaining a royal. In response to the sudden announcement of a vague and evolving plan for the Duke and Duchess of Sussex to move to Canada while remaining part of the royal family, the Trudeau government's response should be simple and succinct: No."
'Welcome but on our terms'
The Toronto Star - Canada's highest-circulation newspaper - took a softer approach to the Royals.
In its editorial, the newspaper said Harry and Meghan were welcome, "but on our terms'.
The paper's editorial board wrote: "It’s up to the government, as representative of all Canadians, to put bounds on any public role that Harry and Meghan might be contemplating in Canada."
They added: "Canada’s version of the monarchy has been thoroughly Canadianized, and there’s really no room for the Sussexes except as private citizens — albeit famous and glamorous ones."
Back to work
Today, the Duke of Sussex is to conduct his first public engagement since announcing that he and his wife Meghan will be stepping back as senior royals.
Harry will host the Rugby League World Cup 2021 draw at Buckingham Palace on Thursday, where he will meet with representatives from all 21 nations taking part.
The duke will then remain in the UK into next week, despite rumours claiming he was preparing to fly to Canada to be reunited with Meghan and baby son Archie