The Rail, Maritime and Transport union general secretary, Mick Lynch, has told Grant Shapps to “tone down the rhetoric and get on with his job”.
Lynch’s comments came as 24-hour rail strikes entered a third day, causing major disruption on train services across Great Britain.
The transport secretary had accused the union of telling a “total lie” over claims he was “wrecking” negotiations by refusing to allow Network Rail to withdraw redundancy threats.
Lynch, who joined workers on a picket line at London’s Euston station on Saturday, said: “We haven’t made any false claims. The railway last week was down by 80%, that has an effect that we don’t particularly want to deploy and they are losing revenue commercially and that hurts them and it hurts our people because they’ve lost their wages. We don’t want that.
“So if Grant Shapps wants to be constructive that’s what he can do. He needs to tone down the rhetoric and get on with his job, which is to settle this dispute.”
Strikers at the central London picket line held up RMT banners and draped flags over the barrier that read “Defend Rail Jobs Pay Conditions”, the PA news agency reported.
The strikes were called as part of a dispute over pay and conditions on the railways, after the government told Network Rail and train operating companies to find savings through “modernisation” to fund pay deals.
Lynch said those in power “have never worked on the tools” and were brought up on a diet of “Latin and Greek”.
“They’re not using the system that they want and they’ve never worked in this type of work,” he said. “Many of them have never run a business but they’ve also never worked on the tools. As my mother would say, they’ve never done a hand’s turn.
“It’s quite odd the people who are running this country are brought up on a diet of Latin and Greek and our members are brought up on a diet of getting up at ungodly times to run the transport system.”
While many rail services were cancelled on Saturday, with disruption expected to continue into Sunday, some trains were able to run in and out of most major destinations.
The RMT has said it had not ruled out taking further industrial action, including more strikes, but any future dates are yet to be confirmed. Unions are legally required to give two weeks’ notice of any strikes so there will not be any for the next fortnight.
A Department for Transport spokesperson said: “The transport secretary has consistently urged union representatives to get back around the negotiating table and agree a deal to bring our rail industry into the 21st century.
“Strikes should always be the last resort, not the first, so it is hugely disappointing and premature that the RMT went ahead with industrial action, which caused significant upheaval to the lives of those they claim to stand up for.”