Penny Mordaunt has rejected a call by Boris Johnson to pull out of the Tory leadership race and back him for prime minister instead, sources close to her have told Sky News.
The Commons leader is understood to have spoken to the former PM as he seeks to shore up support for a return to Downing Street, despite not officially announcing his candidacy yet.
But Ms Mordaunt has chosen to stick with her own campaign, and earlier insisted she was “in it to win it”.
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Those wanting to make the final ballot to win the keys to Number 10 only have until 2pm on Monday to secure nominations from at least 100 Tory MPs.
Ms Mordaunt confirmed she was running on Friday and so far has 24 members publicly backing her, while Mr Johnson has 59.
Both are far behind former Chancellor Rishi Sunak, who had already reached the threshold before announcing he was running on Sunday – and now has 142 supporters.
If all three make it through the first stage of the leadership contest, Tory MPs will vote to chose their favoured candidate.
However, if they fail to unite behind one person, the decision will fall to the wider party membership to decide between the two most popular PM hopefuls.
Mr Johnson was also understood to have held talks with Mr Sunak last night amid rumours they were trying to come to a deal over the leadership – but the meeting appears to have come to nothing.