OTTAWA –U.S. President Donald Trump's racist tweets telling four female congresswomen of colour to "go back" to where they came from are "not how we do things in Canada," Prime Minister Justin Trudeau says.

During a joint media availability with NATO Secretary General Jens Stoltenberg at CFB Petawawa, Trudeau stopped short of calling Trump's remarks racist.

In a series of tweets sent on Sunday, Trump launched into an attack on the elected officials.

"So interesting to see 'Progressive' Democrat Congresswomen, who originally came from countries whose governments are a complete and total catastrophe, the worst, most corrupt and inept anywhere in the world… now loudly… and viciously telling the people of the United States, the greatest and most powerful Nation on earth, how our government is to be run. Why don't they go back and help fix the totally broken and crime infested places from which they came. Then come back and show us how.... it is done," Trump said.

Asked his thoughts on Trump’s comments and whether or not he thought they were racist, Trudeau said: "I think Canadians and indeed people around the world know exactly what I think about those particular comments.That is not how we do things in Canada. A Canadian is a Canadian, is a Canadian and the diversity of our country is actually one of our greatest strengths and a source of tremendous resilience and pride for Canadians and we will continue to defend that," Trudeau said.

Trump's tweets were referring to Democrat members of Congress Alexandria Ocasio-Cortez, Rashida Tlaib, Ayanna Pressley, and Ilhan Omar. All but Omar, a Somalian refugee, were born in the United States. His comments were quickly denounced by Democratic presidential candidates, with Kamala Harris calling it "absolutely racist and un-American."

Trump's tweets appeared to be in reference to the Democrats’ vocal opposition to the conditions in U.S. immigration detention centres and the latest wave of deportations of undocumented immigrants. His remarks have also been viewed as an effort to exploit a rift between the four rookie elected officials and House Speaker Nancy Pelosi over the direction of the party, with Trump suggesting that Pelosi would be glad to see the women leave.

Other world leaders have condemned the comments, with a spokesperson for outgoing U.K. Prime Minister Theresa May calling Trump's remarks "completely unacceptable."

"The President of the United States telling elected politicians - or any other Americans for that matter - to 'go back' to other countries is not OK, and diplomatic politeness should not stop us saying so, loudly and clearly," tweeted the First Minister of Scotland Nicola Sturgeon.

With a report from CTV News' Richard Madan.