Islington North MP Jeremy Corbyn went against his party to support calls for a referendum on UK membership of the European Union on Monday.
Mr Corbyn was one of 19 Labour MPs who backed a motion to hold a public vote on leaving the EU, defying the instructions of party leader Ed Miliband.
Emily Thornberry, MP for Islington South and Finsbury and the Shadow Attorney General, followed the party line.
The motion went before the House of Commons after more than 100,000 people signed an online petition, but was rejected by a majority of 372 after being opposed by all three main parties, despite a significant Tory rebellion.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here