Labour wins Holborn by-election

Labour's Sagal Abdi-Wali beats Green Party leader Zack Polanski to hold the north London seat in a by-election.

Camden council leader Abdi-Wali held the north London seat for Labour, but the party's majority was reduced from 11,572 to 3,364.

At a victory rally, Abdi-Wali told supporters: 'People voted for hope and now we're going to be able to deliver for them. '

The by-election, which was triggered after former Prime Minister Sir Keir Starmer stood down as an MP, had been seen as a key test of whether Labour under Andy Burnham can win over voters who have switched to the Greens.

Speaking to BBC Breakfast after his defeat, Polanski said the result proved his party was 'more of an electoral threat in these seats than we've ever been before'.

He insisted he would stay on as leader despite the result. Polanski is under pressure over his response to a policy motion passed by members at his party's conference that declared Zionism a form of racism.

MP Sagal Abdi-Wali makes housing her priority. Polanski vows to stay on as Green leader as criticism mounts.

Chris Mason: Polanski faces greatest crisis of his leadership so far. Labour's Abdi-Wali secured 45% of the vote, followed by Polanski on 33%. The inner London constituency has been Labour since it was created in 1983, with the party taking at least 40% of the vote at every general election.

In her victory speech at the count in Camden, Abdi-Wali, who came to the UK as a child refugee from Somalia, said her victory was a testament to the success of diversity in the borough.

Later, speaking at a rally alongside Labour Party deputy leader