* Sadiq Khan is Britain's most prominent Muslim politician
* Opposes Trump visit while travel ban remains
* Trip puts queen in difficult position: ex-ministry head
The mayor of London, Sadiq Khan, will tell the top US diplomat in Britain on Tuesday that President Donald Trump's travel ban on people from a list of Muslim nations is prejudiced and will hurt rather than improve US security.
Khan, Britain's most prominent Muslim politician, will make his comments at a meeting of foreign dignitaries, including US chargé d'affaires Lewis Lukens and ambassadors from most of the countries affected by the ban, the mayor's office said.
"Targeting people for no reason other than their faith or their country of birth is cruel, prejudiced and counterproductive," he will say, according to excerpts released to the media.
Khan, a member of the opposition Labour party who was elected mayor last year, has called on Prime Minister Theresa May to cancel a planned state visit to London until he lifts the ban that he signed into force last Friday.
More than 1.6mn UK residents who have signed an online petition against the visit.
May has said the visit, which would include a banquet hosted by Queen Elizabeth, will go ahead, and 90,000 people have signed a counter-petition supporting it.
Peter Ricketts, a former head of Britain's foreign ministry, said he was surprised the invitation had been issued so early into Trump's presidency, and that it would have been possible to invite him without the ceremonials of a full state visit.
"My concern is the queen will have acted on the government's advice as she always does. Clearly there is now a lot of controversy around that," Ricketts told BBC Radio.
"If the current level of protest and opposition goes on then I do think the queen is put in a difficult position."
Sadiq Khan has called on Prime Minister Theresa May to cancel Donald Trump's planned state visit to London.
