German Chancellor Angela Merkel does not believe that US President Donald Trump's order to ban the entry of refugees and citizens from a handful of predominantly Muslim countries is justified by security concerns, her spokesperson said today.

"She is convinced that even the necessarily resolute fight against terrorism does not justify placing people of a certain background or a certain faith under general suspicion," Steffen Seibert said in Berlin.

On Friday, Trump signed an executive order temporarily halting the US refugee programme and banning citizens from seven Muslim-majority countries from entering the US.

A court in New York has since granted an emergency stay against the policy amid protests and dramatic scenes at airports.

A statement outlining Merkel's opposition to the travel ban stressed that the international community is obligated to take in refugees of war on humanitarian grounds under the Geneva Convention.

The chancellor had reminded Trump of that obligation in her phone call with the president yesterday, the statement, which was released on Seibert's official Twitter page, said.

It added that the German government is now assessing what impact the new measures could have on German citizens of dual nationality.

Merkel's 2015 decision to open Germany's doors to hundreds of thousands of refugees and migrants made her a divisive figure on the topic of migration. While many hailed as a hero, others - including Trump - have slammed the policy as misguided and even dangerous.

In an interview with Germany's Bild newspaper and the Times of London ahead of his inauguration, Trump described Merkel's stance on the European migration crisis as a "catastrophic mistake."

- dpa