Latest developments:
ITV News' political correspondent, Carl Dinnen, reports.
As pressure on Jeremy Corbyn to resign increases, the Labour leader has released a video message to party supporters, urging them to "come together".
However, this is at the same time that Labour's deputy leader Tom Watson has said that on Tuesday he will speak to the unions to try and get them to withdraw their support for Mr Corbyn.
Former shadow cabinet member Anglea Eagle has also said she has "the support to run and resolve this impasse", and that she will do if Mr Corbyn "does not take action soon".
The leader of the UK's biggest trade union has said the country is 'riven' as a result of the EU referendum.
Len McCluskey told ITV News that the trade unions can help broker a peace deal and reunite the party now the "coup has failed".
Labour leader Jeremy Corbyn said he would 'reach out' to MPs that oppose his leadership but said they should 'respect democracy'.