One of the Labour Party’s biggest funders and the biggest union federation (Unite) pledged to force a general election if it does not like Theresa May’s Brexit deal.

“Our priority will be to force an early general election which can lead to the election of a Labour government which would, among other things, reach a better deal with the European Union and improved relations with Europe all round,” the Unite motion read, carrying the weight of 1,4 million members.

The union came short of calling for a second referendum, but a motion specifies that members remain “open to the possibility.”

The union’s leader Len McCluskey is a key ally of leader of the Labour Party, Jeremy Corbyn.

Although McCluskey did not commit to a second referendum, he said that Theresa May is “held prisoner” by hardlines Eurosceptic ideologues who want to turn the UK in “the low-wage, deregulated, race-to-the-bottom society of their dreams.”

Jeremy Corbyn has made clear he wants the Labour Party to stand by the 2016 popular vote result; McCluskey did not question this position but made clear the unionists would oppose a “Tory cliff-edge Brexit” to support and employment rights.

Ahead of Labour’s autumn conference, Jeremy Corbyn is under increasing pressure from several MPs, unions and activists for a more combative stance on Brexit.