BREXITEER minister Penny Mordaunt today refused to back the PM's Chequers plan - and said it could change over coming months.
The International Development Secretary insisted she supports Theresa May and wants her to continue in office.
But she undermined the PM by claiming the outcome of Brexit is still unclear despite Mrs May's Chequers proposals.
And she took a coded dig at her boss, warning she must deliver the spirit as well as the letter of the referendum result.
Speaking in London, Ms Mordaunt repeatedly refused to say she supports Chequers - and wouldn't even use the word.
The minister said: "The Prime Minister can count on my support. But what I would say is that we don't know where this is going to end up.
"We are at a critical moment now. The ball is firmly back in the EU's court - we are waiting for them to respond.
"I think that what we need to do is just support both the PM but also Dominic Raab and the negotiating team.
"They are trying to get the best deal for our country and, until we know what that is, I think that is the best way we can help."
Mrs May has repeatedly insisted that Chequers is now the only Brexit deal on the table.
But Ms Mordaunt's comments will encourage Tory Brexiteers who want the PM to put forward an alternative looser trade agreement.
She also piled pressure on Mrs May with a warning she must deliver the "motives and ambition" of the 2016 referendum - and said the Government must not "punish" voters for backing Brexit.
Ms Mordaunt said: "I believe in honouring the result we must also honour the motives and ambitions of that historic decision.
"Over the last year, there has been a mischaracterisation of the British people and their reason for choosing to leave. You'd be wrong to interpret Brexit as protectionist, nationalist or selfish.
"Just as you'd be wrong to interpret the scepticism some of the public have about aspects of UK aid to a lack of love or logic on their part.
"Brexiteers and aid sceptics are not uncaring, selfish little Englanders. Indeed, it is often those very people who give the greatest percent of their income to help others.
"It's just that they believe it's not government that binds nations together. It's trade, and it's our common humanity. It's not government that employs people, it's business, it's not government who has all the power, it's the people.
"It's not government that enables compassion, it's people and their taxes."
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"And if the people tell you what they want they don't want a government to punish them for it. They just want them to get on with it. Government is not the master, the people are."
Ms Mordaunt is one of just two Cabinet ministers who have never publicly backed Chequers, prompting speculation she could quit over the PM's plan.
During her speech today, she also announced new plans - first revealed by The Sun - to put more private cash into foreign aid so the Government spends less.
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