Donald Trump's controversial immigration crackdown will make "no difference" to anyone with a British passport, Boris Johnson has told MPs.
The foreign secretary said he had been assured Britons born overseas or with dual passports would not be affected.
He also dismissed criticism of a planned UK state visit by Mr Trump.
Labour said the government had been slow to respond to Mr Trump's travel ban on refugees and citizens from nations including Syria, Iran and Iraq.
An executive order signed by Mr Trump on Friday halted the US refugee programme for 120 days, indefinitely banned all Syrian refugees and suspended the entry of all nationals from seven Muslim-majority countries, also including Yemen, Sudan, Somalia and Libya.
The White House says a ban is justified on grounds of national security.
It has also indicated that it might extend so-called "extreme vetting" procedures to more countries.