Two Tory big beasts are launching a group campaigning for "radical" policies, amid pressure on David Cameron's leadership.
Former frontbenchers David Davis and Liam Fox will unveil Conservative Voice, urging the party to show "serious ambition".
Although organisers insist the group will work alongside the leadership, the move comes with the Prime Minister struggling to placate Conservative traditionalists.
It emerged over the weekend that an MP was approached to run as a "stalking horse" candidate against Mr Cameron. London Mayor Boris Johnson has also been accused of using his post-Olympics popularity bounce to manoeuvre against the premier.
The new group is intended to unite grassroots Tory activists and more senior politicians who "support the Conservative agenda of individual aspiration, small government, low taxes, a broad rather than deep relationship with Europe, more direct accountability to voters and radical thinking on providing public services and tackling the country's social and economic challenges".
As well as Mr Davis and Dr Fox, other MPs named as backers are Conor Burns, Robert Halfon, Priti Patel and Dominic Raab.
Mr Davis said: "Conservative Voice is the first political initiative in a very long time that provides a home for the professional and voluntary wings of the Conservative Party and who are united in their belief in popular, radical conservatism.
"Our aim is to encourage seriously ambitious policy development and to help improve the party's campaigning edge in really practical ways. Our approach is to work from inside the party and alongside the leadership, and to actively engage with think-tanks, campaigning organisations, academics and business people."
Don Porter, a former chairman of the party's voluntary wing, will also attend the launch in Westminster.
"I am personally very keen to win back former members and voters attracted to Ukip and to start dealing with that party head-on," he said.