Dominic Cummings is accused of using an armed police officer to humiliate sacked aide

The Prime Minister’s all-powerful Brexit chief Dominic Cummings has been accused of using an armed officer to humiliate a female aide by marching her out of No 10 after he sacked her.  

Colleagues claimed that Mr Cummings had used the officer to escort Sonia Khan, 27, embarrassing her over a political feud. 

But Scotland Yard insisted that it was ‘standard practice’ for Downing Street visitors to be escorted off the premises after a meeting. 

Ms Khan, one of Sajid Javid’s top advisers, was fired by Cummings on Thursday evening for allegedly misleading him over the extent of her contact with Philip Hammond – her former boss at the Treasury and an avowed opponent of Mr Johnson’s Brexit strategy. 

The sacking left Mr Javid ‘absolutely furious’ and he confronted an ‘apologetic’ Mr Johnson on Friday to demand an explanation about why Ms Khan had been escorted out of Downing Street by police.

Attention was drawn to the armed officer who escorted Ms Khan from No10, with a former colleague saying that it was done to embarrass and upset a ‘young female aide’.

One ex colleague said: ‘Dozens of visitors leave Downing Street through the front door without a pass every day without being escorted.’ 

Stephen Doughty, a Labour member of the Commons home affairs committee, also said that he would be asking Sir Mark Sedwill, the Cabinet Secretary, and Met Commissioner Cressida Dick to ‘explain urgently whether any protocols or codes of conduct were broken’.

According to the Telegraph, on Friday night, a Metropolitan Police spokesman said: ‘On Thursday, 29 August, a police officer stationed at the door of No 10 Downing Street escorted a woman from the front door to exit gates as she did not have a security pass at the time.

‘This is standard practice if a visitor does not have a pass. The woman was not arrested.’

However, this is disputed by several other people. 

Sources said Miss Khan was escorted from outside the room in which they met, through No10 to the front door of building, and then out to the back exit from the road.  

Meanwhile, a spokesman for Mr Hammond said yesterday: ‘Sonia was a superb special adviser to Philip when he was Chancellor. But she’s a committed Brexiteer and passionate about leaving on October 31. 

‘The idea that she would leak to people trying to prevent No Deal is totally implausible. Where’s the motive?’

The latest update comes as The Mail on Sunday has learned that a former Sky News presenter is at the centre of the extraordinary row.

Poppy Trowbridge, who spent three years as a special adviser to Mr Hammond, has been a prominent figure in the media since leaving Government earlier this year, critiquing Mr Johnson’s Brexit strategy and warning about the risks of a No Deal.

According to sources, when Mr Cummings confronted Ms Khan and demanded to know which allies of Mr Hammond she had recently contacted – including Ms Trowbridge – he first asked her to unlock and hand over her Government phone.

While he was examining its contents he noticed that Ms Khan was scrolling ‘frantically’ through her personal phone deleting messages.

Mr Cummings then forced Ms Khan to surrender her personal handset: although sources say that Ms Khan had ‘managed to clear most of her WhatsApp messages’, Mr Cummings spotted a recent voice call to Ms Trowbridge. It was at that point that he stripped her of her security pass and summoned the police.

Ms Khan was not available for comment yesterday but, ominously for No 10, her friends said she was considering her next steps. 

One said: ‘She is in pieces over this. She is still in shock. It has damaged her career prospects and neither she nor Sajid will let it rest.’