Labour’s ruling national executive committee has approved a plan to double the size of the party’s key disciplinary body, in order to speed up the handling of antisemitism claims.

The backlog of disciplinary cases against party members was one of the concerns raised by Jewish leaders when they met Jeremy Corbyn this year.

At a marathon NEC meeting on Tuesday, it was agreed that membership of the national constitutional committee (NCC), which decides cases, would be doubled, with 14 additional members elected.

A Labour spokesperson said: “Labour’s new general secretary Jennie Formby has made speeding up and strengthening our disciplinary procedures against antisemitism a top priority.

“Labour’s NEC has approved rule changes to expand the size of the national constitutional committee, the party’s autonomous disciplinary body, and other measures to enable them to hear cases more frequently and with fewer delays. These will be put to a vote at conference.”

If the rules are approved, the NEC will also have the power to “approve or amend” the NCC’s guidelines for overseeing claims. And in some cases, where the possible sanction falls short of expulsion from the party, the NCC could make a decision without a hearing.

Some Labour MPs have complained that disciplinary cases are taking too long to resolve, blaming the leadership for failing to take robust enough action, but the NCC is an independently elected body. The new system could result in the NEC exerting more control.

A Labour source said the NEC had also dealt with the remaining backlog of cases, with those that require further action passed on to the NCC for a decision. “No other party body can influence the NCC’s decisions, but if these rule changes pass at conference, the NCC has no excuse for not getting through cases more quickly,” the source said.

The streamlining of disciplinary cases was one of the less contentious issues tackled in an all-day NEC meeting on Tuesday.

Another session on Saturday is due to discuss controversial plans to change the system for electing Corbyn’s successor as Labour leader, and make it easier for party members to eject sitting MPs.

Labour’s annual conference, which begins this weekend in Liverpool, is expected to focus on Brexit, as well as the next stage of Corbyn’s project of transforming his party.

Labour is keen to show it is getting to grips with antisemitism, after the row that raged all summer over the party’s new code of conduct.

The NEC eventually voted to adopt in full the International Holocaust Remembrance Alliance’s definition of antisemitism and all its associated examples this month, alongside a statement defending members’ right to criticise Israel.

Wes Streeting, the Labour MP for Ilford North, said: “I think the party needs to step up several gears to improve the speed and quality of decision-making when it comes to antisemitism complaints. Key gaps in the staffing of the compliance unit is probably a bigger challenge at this stage than the size of the NCC, but at least the problem is being acknowledged. We now need to solve it.”