Jeremy Corbyn has confirmed he will stand down but is prepared to lead his party until a successor is chosen.
Defeated Mr Corbyn did not confirm when an election would be held but said it would likely be the early part of next year.
Mr Corbyn said he is "very sad" at the party's worst general election result in more than 80 years, adding that he has "pride in our manifesto and all of the policies that we put forward".
When asked about his timetable to leave as leader, Mr Corbyn said: "The National Executive will have to meet, of course, in the very near future and it is up to them. It will be in the early part of next year."
Last night he said he would resign as leader of the Labour party - after the party slumped to its worst defeat since 1935.
He said he would not lead the party in any future election campaign.
But he said he would lead the party during a period of "reflection" on last night's result.
Speaking from Islington Town a defiant a Mr Corbyn said he was "prepared to lead the party until a successor is chosen".
Mr Corbyn apologised to those MPs who had lost their seat and said that the election was "taken over by Brexit".
Mr Corbyn was re-elected MP for Islington North, securing 34,603 votes - a majority of 26,188.
But MPs and defeated candidates who said his leadership was to blame for their catastrophic showing and called on him to go.
Veteran MP Dame Margaret Hodge, a long-standing critic, said the result represented the rejection of the entire Corbyn project and that it was time for him to quit.
She said that under his leadership, Labour had become the "nasty party" with anti-Semitism allowed to flourish.
"People just didn't trust the economics, the confetti of promises that was thrown at the public without any clear and honest way they were going to be paid for," she told the BBC.
"People didn't trust us with the national security of the nation. People didn't trust Mr Corbyn with looking after them.
"Labour has become the nasty party. I am one of the victims of that with the anti-Semitism."
Phil Wilson, who lost Tony Blair's former seat of Sedgefield to the Tories, said attempts by the leadership to put the result down to Brexit was "mendacious nonsense".
"Jeremy Corbyn's leadership was a bigger problem. To say otherwise is delusional. The party's leadership went down like a lead balloon on the doorstep," he said.
After losing former Labour stronghold Stoke-on-Trent North, Ruth Smeeth said: "This is a disaster. Jeremy Corbyn should resign now before his own count is in."
Former cabinet minister Hilary Benn said voters simply did not have confidence in Mr Corbyn's leadership.
"Any Labour canvasser will tell you we knocked on too many doors where people said, 'I've voted Labour all my life but I'm not going to vote Labour in this occasion', and they didn't have confidence in the leadership of the party," he said.
Allies of the Labour leader insisted the defeat was down to the inability to overcome differences over Brexit rather than a rejection of Mr Corbyn's radical left wing policy programme.
The party was left with just 203 seats - down from the 262 it won in the 2017 general election and the 243 it held when Parliament was dissolved in November.
Speaking at the Sobell Leisure Centre in Holloway, north London, Mr Corbyn defended his "manifesto of hope" to right social injustices and tackle the climate crisis.
"All of those policies were extremely popular during the election campaign and remain policies that have huge popular support all across this country," he said.
"However, Brexit has so polarised and divided debate in this country it has overridden so much of a normal political debate and I recognise that has contributed to the results that the Labour Party has received this evening all across this country."
