France has discussed with Denmark sending troops to Greenland in response to United States President Donald Trump's repeated threats to annex the Danish territory, French Foreign Minister Jean-Noël Barrot said.

Barrot's comments came as Danish Prime Minister Mette Frederiksen was in the middle of a lightning tour of European capitals to drum up support from allies in dealing with Trump.

Frederiksen was in Berlin and Paris Tuesday morning to speak with German Chancellor Olaf Scholz and French President Emmanuel Macron, respectively, and is set to meet NATO Secretary-General Mark Rutte in Brussels.

"If Denmark calls for help, France will be there," he said. "The European borders are sovereign whether it's north, south, east and west ... nobody can allow themselves to mess around with our borders."

Barrot also said that during a European Union foreign ministers' meeting in Brussels on Monday, his counterparts had expressed their "very strong support" for Copenhagen and "were ready to consider [sending troops]" if needed.