Boris Johnson, the former foreign secretary, has refused to apologise for suggesting Muslim women wearing burkas “look like letter boxes”.
He has come under fire from parliamentary colleagues but rejected calls from Brandon Lewis, Conservative party chairman, to retract his remark.
Theresa May, the UK prime minister, said Mr Johnson’s remarks had “clearly caused offence” and said she agreed with Mr Lewis.
Mrs May said: “I do think that we all have to be very careful about the language and terms we use. And some of the terms Boris used describing people’s appearance obviously have offended [ . . .] I believe women should be able to choose how they dress.”
In an article in Monday’s Daily Telegraph, Mr Johnson wrote that he opposed banning veils in public. But he added it was “absolutely ridiculous that people should choose to go around looking like letter boxes”.
Alistair Burt, a UK Foreign Office minister, told BBC Radio 4’s Today programme there was a “degree of offence” in the MP’s comments.
Mr Lewis said on Twitter that he agreed and disclosed he had asked Mr Johnson to apologise.
An ally of Mr Johnson confirmed he was not willing to do so. “It is ridiculous that these views are being attacked — we must not fall into the trap of shutting down the debate on difficult issues,” the person said. “We have to call it out. If we fail to speak up for liberal values, then we are simply yielding ground to reactionaries and extremists.”
Sayeeda Warsi, the former Conservative party co-chairman and first Muslim woman in the UK cabinet, said Mr Johnson’s remarks were “offensive and deliberately provocative, but very clever politics”.
Baroness Warsi added: “What offends me is that Muslim women are not a convenient political football to be used by old Etonians.”
Mr Johnson has been accused of “fanning the flames of Islamophobia” and described by Labour MPs as a “pound-shop Donald Trump”.
His remarks have also been compared with those made by Steve Bannon, the former adviser to US president Donald Trump.
Stewart Wood, a Labour peer, said on Twitter: “The general view of Boris Johnson’s insulting remarks on Muslim women is that it betrays unthinking Islamophobia.
“More likely in my view is that it was a premeditated remark, from a man enamoured with the Bannon playbook and desperate to be a rightwing populist Tory prime minister.”
When Mr Bannon spent time in the UK recently, he was in touch with Brexit-supporting Conservatives, including Mr Johnson. Allies of the former foreign secretary said he was not in regular contact with the American.
Tim Bale, politics professor at Queen Mary University of London, said Mr Johnson’s remarks were intended to appeal to the grassroots of the party.
“He knows the key to his appeal to Tory supporters is his continued newsworthiness. So anything that gets him attention goes,” he told the Financial Times.
“The terms ‘responsibility’ and ‘good judgment’ aren’t in his vocabulary. What counts is whatever keeps him in the headlines,” he said.
“And that’s because staying in the news — especially if it involves spouting the kind of politically incorrect stuff that appeals to sections of the Tory grassroots — keeps him in the contest to be their next leader.”
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