The Labour Party rejected calls to make a firmer commitment to backing a new Brexit referendum, in a defeat for party's pro-European Union members.

The party's most senior decision-making body, the National Executive Committee, kept Labour's policy of maintaining the "option" of a second referendum.

Jeremy Corbyn's party is heavily split over the question of a second referendum.

A significant number of MPs and most of the party's members want Labour to make backing a new referendum a bigger priority.

However, Corbyn other senior party figures fear that this would alienate Leave voters and cost Labour in future elections.

LONDON — The Labour Party has resisted growing calls from pro-European Union members to explicitly back a second referendum on Brexit.

The National Executive Committee, the party's most senior decision-making body, met on Tuesday to discuss what the party's Brexit policy should be for the upcoming European Parliament elections. It kept its policy of maintaining the "option" of a second referendum.

It also decided against backing calls from the likes of Tom Watson, the deputy Labour leader, and Keir Starmer, the shadow Brexit secretary, for a "confirmatory" vote on any Brexit outcome, including a deal negotiated by Labour.

Labour leader Jeremy Corbyn has for months said the party would support the option of a new referendum if either changing Prime Minister Theresa May's deal with the EU or forcing a general election was not possible.

Corbyn and other NEC members agreed on Tuesday to effectively reendorse this policy, despite intense pressure from within the party to adopt a tougher anti-Brexit stance and make backing a referendum a higher priority.

Following the NEC meeting on Tuesday, a Labour source said: "The NEC agreed the manifesto which will be fully in line with Labour's existing policy: to support Labour's alternative plan, and if we can't get the necessary changes to the government's deal or a general election, to back the option of a public vote."

An official party representative added: "Labour's European Elections manifesto was agreed at the NEC today and it will be published soon.

"Labour is the only party which represents both people who supported Leave and Remain. We are working to bring the country together after the chaos and crisis created by the Tories."

The decision came after nearly six hours of discussions on what the manifesto should include.

Jeremy Corbyn, the Labour leader, and Tom Watson, the deputy leader. Christopher Furlong/Getty Images

The NEC — which comprises Corbyn, numerous shadow Cabinet ministers, trade-union heads, and others — effectively voted to reinstate the party's long-standing policy of supporting a referendum as a means of stopping either a no-deal Brexit or a "damaging" Brexit deal negotiated by May's government.

The NEC had been under intense pressure from a significant number of MPs and the Labour Party's overwhelmingly pro-EU membership to explicitly back a referendum on any Brexit outcome.

Over 30 Labour members of European Parliament and European elections candidates have pledged to campaign explicitly for a new referendum regardless of what the NEC agreed on Tuesday.

Corbyn, his aides, and figures like Labour Party Chairman Ian Lavery fear that becoming an unambiguous pro-referendum party could cost Labour support in upcoming elections, particularly in areas that voted to leave the EU.

Reacting to the decision, Labour MP Bridget Phillipson, who supports the People's Vote campaign for a new referendum, said the party had done "the bare minimum needed" and agreed to "mealy-mouthed wording."

She added: "This means Labour risks demoralising activists, depressing turnout among supporters and decreasing the share of the vote for candidates who — like the overwhelming majority of our party — are fighting for a People's Vote on any Brexit deal."