Boris Johnson has been told to "back off" so Rishi Sunak can get on with sorting out the Brexit mess.
The attention-loving ex-PM is accused of fuelling dissent as ministers race to agree new trading arrangements for Northern Ireland.
Guto Harri, who served as his director of communication in No10, warned there would be grave consequences if Mr Johnson jeopardised a deal.
He told the News Agents podcast: "If we don't have civil war in Northern Ireland, if we don't have a trade war with the Europe, if we manage to leave everybody sufficiently not too dissatisfied then that is a big prize in the current situation.
“I would urge anyone around Boris Johnson who thinks it’s clever to stir things over this to just see the bigger picture, to back off and to let the people in charge try and nail this one.”
Mr Sunak is under pressure to get on and seal a deal on Brexit as his Tory backbenchers behave like rats in a sack.
Loud-mouthed Eurosceptics have warned the PM they will revolt if he fails to deliver what they want.
Ministers have been locked in talks with the EU for more than a year as they try to iron out issues with Boris Johnson’s botched Brexit deal.
They appeared to inch closer to an agreement on changes today as Foreign Secretary James Cleverly held talks with the EU’s Maros Sefcovic on the telephone.
The pair will meet later this week, although a day has not yet been set.
Keir Starmer today urged Mr Sunak to give MPs a vote on any new deal as he reaffirmed his offer of Labour support to get it through the Commons amid signs there could be a rebellion from some wings of the Tory party.
But Downing Street declined to commit to a vote, with the PM’s spokesman only saying: "You will hear more from us should an agreement be reached with the EU that reaches the challenges the Prime Minister has set out."
Speaking on a visit to Thurrock in Essex, the Labour leader said: "I think it should be put to a vote, and I'm very clear to the Prime Minister I will put the country first and the party second and he should do the same."
Veteran Tory Eurosceptic Sir Bernard Jenkin said that any deal which did not lead to a return to powersharing at the Stormont Assembly by the DUP would be "completely disastrous".
"If it doesn't get the support of both communities in Northern Ireland it is just going to make things worse because it will cement in place an agreement that has destroyed powersharing in Northern Ireland," he told Times Radio.
Sammy Wilson, the DUP chief whip at Westminster, accused ministers of going into the negotiations with the EU with "an attitude of defeat" and said that he did not expect to see a deal announced this week.
* Follow Mirror Politics on Snapchat, Tiktok, Twitter and Facebook.
