The biggest rail strike in three decades is expected go ahead after last-ditch talks failed, the RMT union said.
A walkout by 40,000 workers on Tuesday, Thursday and Saturday will cause “total misery”, according to Transport Secretary Grant Shapps.
Mr Shapps said the strike was “totally wrong” and would inconvenience millions – including those like his own daughter who are taking exams.
The action is the result of a dispute over pay, jobs and conditions. The RMT is asking for a pay rise of 7% – lower than inflation but higher than that being offered by employers.
RMT general secretary Mick Lynch said latest offers from publicly-owned Network Rail and private train operating companies had been rejected. He suggested the employers’ hands had been tied by ministers.
Mr Lynch blamed Mr Shapps for cutting billions of pounds in funding for public transport. The union also claims the government is trying to force through thousands of job cuts.
“The fingerprints of Grant Shapps and the DNA of Rishi Sunak are all over the problems on the railway,” he said.
Asked if industrial action could last for months if a deal is not reached, he added: “I think it will, yes.”
But Mr Shapps said: “The crazy thing about this strike is it was called by the union bosses on false pretences that there would be no pay rises. That was never the case.
“They called a strike that will inconvenience millions this week. It’s totally wrong, totally unfair.”
A Downing Street spokesperson said of the RMT announcement: “This is deeply disappointing. It’s destructive that these self-defeating strikes will take place this week.”
Boris Johnson described the strike as an “act of self-harm for rail workers”.
“School children are at risk of exam disruption, commuters may have to forego their office once more, and families enjoying a summer’s day in the city will no doubt face interruption,” the prime minister told the Evening Standard.
Earlier, Simon Clarke, Chief Secretary to the Treasury, warned that people should prepare for “very substantial disruption” as the start of strike action loomed.
But he said that the “evil of inflation” meant that workers were going to have accept below-inflation pay increases, showing “collective, society wide responsibility” and “sacrifice”.
The strikes represent what some fear could be the start of months of industrial strife, with other workers including teachers also potentially taking action later this year.
Mark Serwotka, general secretary of the PCS union representing civil servants, said his union was balloting 150,000 members over action in September and teachers were also looking at possible strike ballots in the autumn.
He told Sky News: “We will see high levels of industrial action unless the government recognise that frontline public sector workers who kept the country running during the pandemic cannot be expected to have a 2% pay rise when inflation is forecast to be over 11%.”
Labour’s shadow transport secretary Louise Haigh said: “We want to see passengers avoid disruption but of course we understand and support rail workers rights to fight for a fair pay settlement.”
Andrew Haines, Network Rail’s chief executive, said: “No strike is inevitable until the moment it begins, but sadly disruption tomorrow is guaranteed so we’re asking passengers to plan ahead and only travel by train if necessary.”
A further flashpoint between the government and unions could come this week as the government moves forward with a plan to repeal a ban on agency workers being employed to step in for strikers.
Business secretary Kwasi Kwarteng said: “Repealing these 1970s-era restrictions will give businesses the freedom to access skilled, temporary staff at short notice.”
But the move was strongly resisted by unions.
It was also rejected by the Recruitment and Employment Confederation, representing the recruitment agency sector, which issued a joint statement with the TUC calling for the “unworkable” plan to be abandoned.
They said at a time when vacancies stand at 1.3 million, a record high, agency workers picking jobs were very unlikely to choose a role that will involve crossing a picket line.
TUC deputy general secretary Paul Nowak said: “Just a few months ago Grant Shapps slammed P&O for replacing experienced workers with agency staff. But now he’s proposing to do the same on railways.”