London | Up to four of the 10 Conservative MPs who have secured enough support to contest the party leadership - and vie for the prize of becoming Britain's prime minister - could be pushed out of the race this week, when the first of several votes takes place on Thursday.

On Monday (early Tuesday AEST) the senior Tory MPs overseeing the contest unveiled the list of contenders for a series of ballots of the party's 313 parliamentarians, at the end of which the last two candidates standing will embark on a month-long campaign and postal vote among the 120,000-plus Conservative grassroots members.