Boris Johnson has been warned that removing the Irish backstop from the Brexit Withdrawal Agreement may not be enough to guarantee the support of hard-line Eurosceptic MPs.
Longstanding Brexiteer MPs David Davis and Sir Bill Cash have hinted that they might not back a deal agreed by Johnson if he only alters the controversial Northern Ireland border plan in a "cut and paste operation".
The news came as Johnson returned from talks with French President Emmanuel Macron and German Chancellor Angela Merkel aimed at convincing EU leaders to remove the controversial backstop from the Withdrawal Agreement.
UK Broadsheet, the Times reports that Johnson had been "buoyed" by his meeting with Macron, who said that while the backstop was "indispensable", the two sides may be able to "find something smart within 30 days if there is goodwill on both sides".
However Macron’s comments were also interpreted in Europe’s capitals as simply placing the onus firmly on Johnson to come up with a clear alternative arrangement to the backstop; a task that the UK government has so far been unable to provide.
But, speaking to the Telegraph, David Davis the former UK Brexit Secretary suggested a string of additional changes to the Withdrawal Agreement would be needed to win him over.
Those included calls for the UK to refuse to pay the full £39bn Brexit divorce bill, as well as stronger curbs on the jurisdiction of the European Court of Justice(ECJ).
Asked if he would back the agreement, Davis said: "I’d argue for contingency on the money. I’d argue for tighter limits, timetable limits, sunset clauses on the ECJ and things like that. I’d have a small shopping list.
"It wouldn’t be a ridiculous one, but one I think that any serious European Parliament and any European Council that wants a deal could go with.
"We will be governed for a number of years by the other 27 member states under the existing draft withdrawal agreement... even with the backstop removed" UK MP Sir Bill Cash
I would be insistent that they make the bill - the £39 billion, the second half of it - contingent on progress on the future economic partnership."
Meanwhile Sir Bill Cash, who chairs the UK parliament’s European Scrutiny committee, warned: "You can't restore self-government as a cut and paste operation and I am sure they understand that - taking parts of the withdrawal agreement.
"We will be governed for a number of years by the other 27 member states under the existing draft withdrawal agreement... even with the backstop removed."
But Conservative MP Greg Hands, who has penned a 272-page report on alternatives to the backstop, said his plans - which include the use of 'trusted trader' schemes and checks away from the Irish border - could be "brought in quite quickly".
And he talked up the possibility of avoiding a hard border in Northern Ireland "without remaining half-shackled to Brussels for ever".
Writing in the Daily Mail, he said: "It doesn't mean the EU is yet convinced. It just needs both sides to grasp the opportunity."