Tory chairman Francis Maude has told shadow cabinet critics of David Cameron to "shut up or leave" the front bench.
In an interview with the Parliamentary Monitor, Maude responds to off-the-record briefings against the Conservative leader.
For dissenters Maude has a simple message: "leave".
He attacked the unnamed shadow cabinet member who derided David Cameron's trip to a Norwegian glacier in the midst of the local government election campaign as "barmy" and a "gimmick".
In an ultimatum to those seeking to destabilise the leadership, he said: "It is obviously very unhelpful if anyone in a senior position in the party makes disobliging remarks to the media.
"That is a habit we thought we had grown out of and we need to grow out of it.
"Unattributable briefing and that kind of stuff is just pathetic and should not happen.
"They should just shut up, get on with the job or perhaps even better leave. If they don't like what is being done then being a backbench member of parliament is a perfectly honourable thing to do."
Despite the backlash and indications of slipping back in the opinion polls Maude insists that the momentum remains with the modernisers.
"The honeymoon is not over. Ok we are not far enough ahead in the polls to win an election but we have significantly improved from where we were flatlining for 14 years. So are we in better shape? Yes we emphatically are."
And for Maude, Cameron's personal profile is till a big bonus for the party. "I think David still attracts an extraordinary amount of attention, he's still a very interesting figure for the media and the public and he does reflect and represent change. There'll be much more from him."
