Boris Johnson and Amber Rudd will phone their US counterparts
Boris Johnson and Amber Rudd have been told to call the United States following widespread condemnation of an emergency executive order which has meant hundreds of people with visas and green cards have been turned away from the US since Friday.
Citizens from Iran, Iraq, Syria, Sudan, Libya, Yemen and Somalia are banned for 90 days and all refugee admissions have been suspended for 120 days under the "extreme vetting" order.
Number 10 sources said the Prime Minister's order demonstrated how seriously she is taking the issue.
Mr Johnson and Ms Rudd have been told to raise particular concerns the ban could have on UK nationals.
Downing Street sources added Mrs May was "absolutely determined" to respond to the fears of Britons over the ban and she does "not agree" with the controversial measures.
Britons with dual nationality are part of the ban and there are concerns UK passport holders born in the seven designated countries may also be banned.
Olympic champion Sir Mo Farah, who was born in Somalia, and Iraqi-born Tory MP Nadhim Zahawi, are two of the most high-profile Britons affected by the ban.
This is a breaking story.
Please refresh or return to the page for updates…