Sir Marcus Fox, chairman of the 1922 Committee, will in the New Year propose that leading officers begin in earnest to examine options for change to the rules under which an incumbent leader can be replaced.
Sir Marcus has already consulted his predecessor Cranley Onslow about the options covered during the last review, which followed Lady Thatcher's departure in 1990. That resulted in the present requirement that a contest can only be held if 10 per cent of the parliamentary party signify in writing that they want such a contest.
One member of the 1922 executive said that "nothing will be barred" in an examination of the present leadership rules, and that the officers will not be rushed into making early recommendations.
These could include removing the right to challenge a sitting prime minister for the leadership at all, if he is of sound mind, or raising the proportion of MPs required to demand a contest.
Some senior Tories argue, however, that the increasing threat of leadership challenges adds to turmoil within the party and unnecessarily destabilises the party at the expense of its electoral interests.