Dominic Raab has said the government “can’t allow” the unions to “win” the argument over rail strikes.
Talks are set to resume on Wednesday a bid to resolve the bitter dispute over jobs, pay and conditions.
Around 40,000 members of the RMT union at Network Rail and 13 train operators are involved in the industrial action. RMT members on London Underground also went on strike on Tuesday.
Speaking to Sky News on Wednesday morning, Raab said there had to be “pay restraint” in the public sector to stop inflation spiralling higher.
“That will only undermine the pay packages of workers, particularly the most vulnerable workers, for a longer period of time,” he said.
“We can’t allow, I’m afraid, the unions, in this very militant way they have proceeded, to win this argument.”
RMT general secretary Mick Lynch said the turnout at picket lines had been “fantastic” and had exceeded expectations in the union’s campaign for job security, defending conditions and a decent pay rise.
“RMT members are leading the way for all workers in this country who are sick and tired of having their pay and conditions slashed by a mixture of big business profits and government policy,” he said.
“Now is the time to stand up and fight for every single railway worker in this dispute that we will win.”
The rate of inflation rose again in May, remaining at 40-year highs and deepening the squeeze felt by households across the UK, the Office for National Statistics (ONS) has said.
The rate of consumer prices index (CPI) inflation rose from 9% in April to 9.1% in May.