For some trade union leaders, the general election on 8 June means subordinating the struggles against cuts to getting the vote out for Labour. Some have argued that calling any action in the run-up to the election would be wrong because "everyone will be canvassing for Labour".
But PCS union general secretary Mark Serwotka told Socialist Worker that resistance must be increased - not put on hold.
"The moment the election was announced the PCS put out a statement saying we should use the election to step up our campaigning," he said.
"With the Equality and Human Rights Commission dispute, we've just authorised 20 days of strikes starting in two weeks' time. The first strike will be on 15 May.
"There are offices in Manchester, London, Glasgow and Cardiff. Each office will be out for five days on a rolling programme.
"In our campaign against DWP office closures and jobcentre closures we've called on people to increase their campaigning, not decrease it."
Serwotka said the election was a "really good chance to hurt the Tories".
But he added, "We also know that we need strong unions - we can't just rely on the election result.
"The more people we mobilise the more open people will be to the kind of politics Jeremy Corbyn is putting forward."
Serwotka spoke at a May Day rally in London today, Monday, and called for a vote for Labour. He said it was the first time in decades he had done so. "The reason I've done that is because what is on offer now is radically different from anything we've heard from Labour since, I think, 1983," he said.
But Labour has got a big job on its hands to win. And Serwotka stressed that unions mustn't simply put all their hopes in getting a Corbyn-led government elected.
"I want more than anything a Jeremy Corbyn government," he said. "It's absolutely right to try and maximise the vote for Labour. But it's a fool who doesn't plan for every eventuality.
"Unions must also plan now for the possibility of a new Tory government and the onslaught that will mean.
"We have to fight for public sector pay and against austerity. That means unions fighting together.
Serwotka added that there will be a need to defend Corbyn's left wing policies if Labour loses the election. "Some people within the Labour movement are planning a backlash against Corbyn if he doesn't win," he said.
"They'll argue that we need to return to the austerity-lite politics that we had before. We've got to be on the front foot and argue that what Corbyn is offering is the right thing."
Serwotka stressed that there is no shortage of things to fight over, such as the public sector pay cap which is in place until 2020. "We need to plan now for TUC-wide action to defeat that if the Tories remain in power," he said.
He added, "The trade union movement needs to step up its game.
"Unions haven't worked together in a meaningful way since the strikes of 2011. We need to see a repeat of that kind of action, coordinated across as many unions as possible. That's the way to defeat the pay cap.
"Our focus is to build coordinated action but to call whatever we can if we don't get it.
"We called protests at 300 sites on 31 March. We're calling another one in June. We're initiating a pay claim for an increase of 5 percent or £1,200, whichever's greatest.
"We'll do that on our own if necessary, but it'll be hard. The message we're taking to other unions is, we need to fight together."