Former adviser to Theresa May, Katie Perrior, has said James Duddridge, the MP who submitted a letter of no confidence in Mrs May, has done “the lowliest thing”.
In his letter to the chairman of the Conservative backbench 1922 Committee, Graham Brady, Mr Duddridge - who served as a whip and junior minister under David Cameron - said the Conservatives need "a strong leader, someone who believes in Brexit and someone to deliver what the electorate voted for".
"The Prime Minister seems incapable of doing this. I have not met a single MP who thinks she will lead us into another election after the last disastrous snap election."
"I write this with heavy heart, however we now need a proper leadership election and to move on."
- Read more: Conservative MP submits letter of no confidence in Theresa May minutes before her speech
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But Perrior wasn’t impressed by his tactics.
“She’s a unionist at heart, she loves the nation, she wants to do the right thing. It’s a public duty of service, and she ain’t handing it over to Boris Johnson without a fight, believe me,” she told Mike Graham.
“I’ve got no confidence in James Duddridge!” she continued.
“I’d never heard of him until about five minutes ago. That is the lowliest thing you can do, when your Prime Minister is about to speak in an hour’s time, to submit a letter - big wow.
‘They’re the kind of people, quite frankly, who I don’t want in the Conservative Party.”
'The plan is Boris'
She added that her feelings weren’t from a sense of loyalty to Mrs May.
“Not because I think Theresa May’s great or that she’s been the best Prime Minister - you know I’ve been on this show enough times saying what I think is wrong with her strategies,” Perrior said.
“He can write as many letters as he wants, but he’s going nowhere fast.”
Mr Duddridge also expressed support for Boris Johnson on Twitter on Tuesday, writing: "Turns out there is a plan. That plan is Boris".