SIR Keir Starmer has been warned by another of his own MPs against grubby backroom deals that betray Brexit.
Labour Red Waller Jonathan Brash fired a shot across the PM’s bows, saying any return to the customs union or single market would fly in the face of the party’s manifesto.
And the Hartlepool MP said it would trample on the Leave vote — backed strongly in towns like his.
He spoke out after the PM said he hoped to drag Britain back to Brussels’ orbit and shackle us to more single market rules.
There are also fears a new post-Brexit trade bill being prepared will go far further than stated.
It could hand ministers broad powers to align Britain with the EU across many sectors.
Mr Brash told The Sun: “There is a clear line I won’t cross.
“I don’t believe in sneaking Britain back into the single market or customs union.
“That would be dishonest, break our manifesto commitment and further erode trust in politics.”
Another Labour MP in a Brexit-voting constituency warned the UK would be left as “rule-takers with no say”.
The PM has ruled out joining any Brussels economic bloc.
But he says he plans to explore deals if the UK stands to benefit.
