Theresa May has slapped down anonymous MPs who used violent imagery to describe a possible coup to unseat her.
Weekend newspapers reported Tory backbenchers saying the Prime Minister would be “knifed” and that she should “bring her own noose” to a meeting with MPs to discuss her Brexit plans.
The PM’s official spokesman said Mrs May expected those in public life to avoid “dehumanising” and “derogatory” language.
“I don’t intend to dignify those specific anonymous comments with a response,” the spokesman told a regular Westminster media briefing.
“The Prime Minister has always been very clear that we must set a tone in public discourse that is neither dehumanising nor derogatory.
“Personal vitriol has no place in our politics.”
The vicious attacks marked the start of what is expected to be a tough week for the Prime Minister, with some observers speculating that the number of MPs calling for her removal may reach the 48 figure which would trigger a vote of no confidence.
Mrs May was due to tell MPs that the UK’s Brexit deal is 95% complete and that “important progress” has been made on issues like security, transport and services since last month’s fractious summit in Salzburg.
In a Commons statement after talks with EU leaders in Brussels, the Prime Minister will say the “shape of the deal across the vast majority” of the withdrawal agreement is now clear.
Protocols have been developed on how Brexit will affect Gibraltar and the UK’s military base in Cyprus.
“And all of this, from the last three weeks alone, is in addition to the agreements we had already reached,” she will say.
Mrs May spoke with Cabinet colleagues in lengthy telephone conference calls over the weekend, which Downing Street described as a chance to “give an update on the negotiations”.
She will tell the Commons that “taking all of this together, 95% of the withdrawal agreement and its protocols are now settled”.
But she will add: “As I set out last week, the original backstop proposal from the EU was one we could not accept, as it would mean creating a customs border down the Irish Sea and breaking up the integrity of the UK.
“I do not believe that any UK prime minister could ever accept this. And I certainly will not.”
Furious backbenchers warned the Prime Minister that she is “drinking in the last chance saloon” after tensions flared over her negotiating strategy following a Brussels summit.
But senior Brexiteer Chris Grayling called for calm, warning of the danger of Britain leaving the EU without a deal.
Asked about a possible no-confidence vote, the Transport Secretary told BBC Radio 4’s Today programme: “This is really a moment for calm, level heads.
“We have got to get through the last bit of negotiation. There will be a vote in Parliament that follows.
“The reality is that, if the deal on offer is something that can’t get through Parliament, we will end up in a no-deal situation, so it is in everyone’s interest, the European Union and us, to make sure that what we agree is something that both sides can accept.”
Former Cabinet ministers Iain Duncan Smith and Owen Paterson denied undermining the Prime Minister after meeting the EU’s chief Brexit negotiator, Michel Barnier, in Brussels.
Mr Duncan Smith said: “We are presenting some ideas which we think are constructive and we had a constructive discussion.
“Now we are going to go back and talk to the Government about it.”
He added that whoever briefed in violent terms about he Prime Minister’s future “needs to have the fullest weight of the Conservative Party upon them”.
“It has nothing to do with our politics, it has nothing to do with this issue,” he told reporters in Brussels, adding that Mrs May had his “full support”.
Asked if the EU was making contingency plans for a change of political leadership in the UK, European Commission spokesman Margaritis Schinas said: “As to political developments in Whitehall, this is for Whitehall, not for the Berlaymont (the EC’s Brussels HQ).”
Labour has warned Mrs May that it will not back her Brexit blueprint when it reaches the Commons.
Shadow Brexit secretary Sir Keir Starmer said there is a “real lack of confidence” that Mrs May can bring back “anything by way of a good deal”.