Labour Party membership has plunged by more than 17,000 since the start of the year, according to a new report.
The three per cent drop in paying supporters adds to the pressure on Jeremy Corbyn over his handling of antisemitism allegations.
Hundreds have resigned over the crisis engulfing the party and many more have not renewed their direct debits, according to internal figures seen by The Times.
The report emerged as the Labour party stepped up its campaign for the local council elections in May by appealing for new members on Twitter.
Membership reached a peak of 570,000 after the general election but now appears to be falling.
London alone lost 3,500 members in the last three months, with the North West reporting a fall of 2,000.
Meanwhile the Corbyn-supporting campaign group Momentum has claimed that it added 600 members in the past week.
Mr Corbyn admitted there were "pockets" of antisemitism in Labour and apologised for the "pain and hurt" caused to Jewish people.
The latest row erupted after it emerged he had defended an east London mural which depicted wealthy Jews playing Monopoly on the backs of workers.
Mr Corbyn's key ally Christine Shawcroft resigned from the party's National Executive Committee (NEC) after it emerged she had defended a council candidate accused of Holocaust denial.
In an attempt to defuse the crisis Mr Corbyn's Facebook account was deleted this weekend following claims he joined supporters' groups that contained antisemitic comments.
