Owen Smith's campaign to dethrone Jeremy Corbyn as Labour leader has been given a significant boost after the GMB Union endorsed threw its support behind the Welsh MP. The union, which represents more than 622,000 workers, is the third largest behind Unite and Unison.
The endorsement comes after 60% of GMBs who took part in a ballot, administered by the administered by independent agency Electoral Reform Services, voted for the former shadow work and pensions secretary.
"The Labour Party is at a crossroads. I'm under no illusions that we're living through dangerous political times – the like of which I haven't seen during my three decades in our movement. It's time for us to face up to reality," said Tim Roache, the general secretary of GMB.
"GMB balloted our members because this kind of decision shouldn't be taken from up on high. We're a democratic organisation here to serve our members' interests. I was determined that our members would have their say. And they've had it.
He added: "I'll proudly campaign alongside Owen in the coming weeks and months to deliver on his pledges to end the public sector pay freeze, to support defence workers, to invest in health and industry, and to build an industrial strategy – these are bread and butter issues for the people I represent.
"But we can only tackle them if we're in government. That's the end game and I hope whatever the final result, the Labour Party will unite when all this is over. GMB members cannot afford for Labour to be talking to itself in a bubble for the next five years while the Tories run riot through our rights at work, our public services and our communities."
The union, which represents thousands of workers in the defence industry, is pro-Trident like Smith, while Corbyn is life-long opponent of nuclear weapons. The endorsement comes after the Musician's Union, steel workers' union Community and shopworkers' union Usdaw backed Smith.
"It's a great honour to receive GMB's nomination to be the next leader of the Labour Party after a consultation with its members," Smith said.
"At the heart of my campaign are commitments to strengthening our trade unions, ending exploitation and delivering greater equality.
"I look forward to working with the GMB, its members and all in the labour movement to tackle inequality, invest in strong public services, and for Britain to have trade union and workers' rights that are the envy of the world."
But Corbyn remains favourite to win the leadership contest. The left-winger has the support of transport unions Aslef and TSSA as well as Unite and the Communication Workers' Union. Non-Labour affiliated unions the PCS and RMT also support Corbyn.
Unison, the UK's second largest trade union, is currently conducting a non-binding consultation of its members over who to endorse in the Labour leadership election.