MPs are now voting on whether Culture Secretary Jeremy Huntshould face an inquiry.
The PM's spokeswoman has confirmed that David Cameron will vote.
We are expecting the Tories to win this vote even though the Lib Dems are abstaining.
MPs voted by 290-252 against a Labour motion calling for an investigation into Jeremy Hunt's handling of the BSkyB takeover bid.
Nick Clegg has laid bare a coalition rift by revealing that he wants the PM to launch a probe into Jeremy Hunt's handling of the BSkyB bid.
The Liberal Democrat leadership has asked its members to abstain in a debate over Jeremy Hunt's behaviour during the BSkyB bid process.