Grant Shapps has sought to bolster his campaign to become prime minister with a tweet condemning strike votes by train drivers.

After members of the Aslef union working for eight train operators voted overwhelming to stop work in a pay dispute, the transport secretary tweeted: “Unions linked to Labour have announced train driver strikes.

“On a salary of almost £60,000, it isn’t fair for train drivers to hurt those on lower wages with more walk-outs.

“As prime minister, I would stand up to the unions and make it harder to hold our country to ransom.”

Mick Whelan, general secretary of Aslef, said: “We don’t think we’re special; we believe no worker in this country should put up with pay cuts year after year just because this government has allowed inflation to rise.

“Whatever happened to the Tory wish for good, well-paid, jobs? Obviously that’s only for the CEOs, not for the workers doing the job.

“And, don’t forget, if a train driver doesn’t get a cost of living increase, it won’t mean that a nurse, or care worker, or cleaner will get one. This isn’t – or shouldn’t be – about setting one worker against another.

“We’re happy to talk to anyone to do a deal and make sure Britain’s railways aren’t disrupted. The government is restricting what the operators can offer, but then refusing to get involved in negotiation.

Mr Shapps maintains that the pay disputes across the rail industry are a matter for the unions, train operators and Network Rail to settle.

Last month, members of the RMT union brought most trains in Great Britain to a halt with the first national rail strikes for three decades.

A skeleton service operated on about half the network.

The RMT general secretary, Mick Lynch, said: “Grant Shapps needs to stop messing around with his doomed Tory leadership bid and get back to focusing on resolving this dispute.”

The 2019 Conservative manifesto for the general election promised: “We will require that a minimum service operates during transport strikes.”

Nearly three years on, the government says it is working on the required legislation.

Read More