Conservative Sir Nicholas Soames has told Tory colleague John Redwood to "bugger off" over demands backbenchers listen to party members when deciding which way to vote in the upcoming European Union referendum.
The spat also descended into an argument between Sir Nicholas and ITV's political editor Robert Petson.
On Monday, Redwood said he had emailed Tory MPs to tell them they must back Brexit if they had claimed to be eurosceptic at the general election.
"This referendum will be a defining moment for MPs. We will be judged for several Parliaments to come by what we do and how we vote. Some colleagues have implied that as it is the people’s choice their vote can be a private matter. This is unrealistic," he said.
However Sir Nicholas, the MP for Mid Sussex, who is in favour of Britain's membership of the EU, did not take kindly to the advice.
I must say to be told how to vote in Referendum by J Redwood in an email to colleagues marks a new low in my life in the House #buggeroff— Nicholas Soames (@nsoamesmp) February 15, 2016
Peston, who commented on Sir Nicholas' language, was the next victim of Sir Nicholas' sharp Twitter-tongue.
@Peston get a haircut put on a tie and generally smarten up— Nicholas Soames (@nsoamesmp) February 15, 2016
@Peston and hands out of pockets— Nicholas Soames (@nsoamesmp) February 15, 2016
Peston replied simply:
Errr. Eff off https://t.co/O6SW3FeZbF— Robert Peston (@Peston) February 15, 2016
David Cameron angered many Tories who want Britain to leave the EU after he told his MPs to vote with their "heart" and ignore eurosceptic party members.
"Don't take a view because of what your constituency association might say, or you're worried about a boundary review, or you think it might be advantageous this way or that way, do what's in your heart. If you think it's right for Britain, then do that," he said.
Today Downing Street indicated the prime minister may fire the starting gun on the referendum at the end of the week by holding an unprecedented meeting of the Cabinet on Friday.
It is expected that once the Cabinet meets, Cameron will allow ministers who wish to campaign for Britain to leave the EU to speak their mind in public ahead of the referendum which could be held on June 23.
Work and Pensions Secretary Iain Duncan Smith, Commons Leader Chris Grayling, Culture Secretary John Whittingdale and Employment Minister Priti Patel are all expected to campaign for Brexit once they are free to do so.
Boris Johnson, who has been courted by both 'Remain' and 'Leave' campaigns, said on Sunday he will "come off the fence with deafening éclat" once he makes up his mind which way to vote.
John Redwood's email to MPs in full
Be true to your electors! If you told them you were Eurosceptic, then vote to leave the EU in the referendum. Your supporters backed you because they want our democracy restored, with powers of self government returned. They will feel very let down if you do not help them get the UK out of the EU at the referendum.
This referendum will be a defining moment for MPs. We will be judged for several Parliaments to come by what we do and how we vote. Some colleagues have implied that as it is the people’s choice their vote can be a private matter. This is unrealistic. If you claimed to be a Eurosceptic to get selected and elected you now have to vote to leave. It is important to listen to the members of our party who turned out to help you win your seat.
We live in an age when traditional political parties are mistrusted by many electors. One of the main reasons is their fear – or in the case of some parties their experience – that promises are not kept or important views are overturned once in office. It is crucial that we do the right thing by our voters on this most important of matters. This is a time to put country before party, and the public interest before any personal interests. Brussels is a bureaucracy run by bureacrats for bureaucrats. Many of those who voted for free trade with the EEC dislike the excessive regulatory interventions of the single market, and never imagined they were voting for a government of the EU with its own currency, anthem, President, borders, foreign policy and soon to have its own Treasury.
We know more than enough about the prospective deal to know that it falls far short of the words of the Prime Minister’s Bloomberg speech, where he rightly talked about restoring Parliamentary control over the things that matter to our voters. His well meaning efforts to negotiate a compromise that the UK can live with has simply illustrated the sad truth that the UK can no longer decide for herself the most basic things like how much we pay in benefits, who we invite into our country or what taxes we levy.
We Conservative Eurosceptics have rightly highlighted the dangers of having to ask permission to make even modest changes to our spending plans, our taxation and our borders. Those of us in the Commons at the time united to oppose the Nice, Amsterdam and Lisbon treaties that gave away far too much of our power to govern ourselves. David Cameron himself led us in our opposition to Lisbon.
The deal before us does nothing to change a single word of any of these treaties. Not a single veto is returned to the UK that was wantonly given away. In future without a veto the UK government, Parliament and people can be outvoted by other EU states, giving us laws, taxes and policies we do not want. The well intentioned efforts to give us a bit more freedom over the payment of benefits in certain circumstances is not proof against a European Court case reversing it, nor against a future change of policy by a majority of EU members.
There is no half way house or middle way. The vote is simple. Stay or leave. If like me you want to be governed by a democracy, where government is of the people, by the people, for the people, there is only one option. UK democracy is incompatible with EU membership. Your voters and your party members look to you now to lead them. They will watch carefully, and will expect to see you now do what your words at the selection conference and at the election implied you would. We cannot just be Eurosceptic for the election.