A Danish newspaper refused to apologise to China on Tuesday over a satirical cartoon it ran about the deadly new virus that has killed dozens and infected thousands more, with the prime minister stepping in to defend freedom of speech.

The cartoon, published in Jyllands-Posten on Monday, depicted a Chinese flag with the yellow stars normally found in the upper left corner exchanged for drawings of the new coronavirus.

China's embassy in Denmark called the cartoon "an insult to China" that "hurts the feelings of the Chinese people".

The embassy said the cartoon crossed the "ethical boundary of free speech" and demanded that the paper and cartoonist Niels Bo Bojesen "reproach themselves for their mistake and publicly apologise to the Chinese people".

Danish Prime Minister Mette Frederiksen said freedom of expression in Denmark includes cartoons.