Former Cabinet minister Kate Hoey has become the second Labour MP to demand the resignation of Gordon Brown.
A secret letter outlining Tory plans towards the EU has complicated efforts to secure a Conservative-Lib Dem coalition.
Nearly half the public wants some form of proportional representation for future elections, according to a new poll.
There are growing signs of rebellion against David Cameron's rule within the Conservative party after he failed to secure a majority at the general election.
Nearly two-thirds of voters believe Gordon Brown should have conceded defeat on Friday and quit No 10, according to a poll.
A coalition between The Conservatives and the Liberal Democrats looks to be on the rocks after senior Tories set their face against electoral reform.