Mick Lynch has called for unions across Britain to “coordinate action” as the country was hit by the biggest rail strike in a generation.
The general secretary of the Rail, Maritime and Transport union said other trade unions needed to “synchronise”, arguing that the British worker needed a pay rise.
Lynch also said the RMT would go on strike again if their issues are not settled as he stood on the picket line outside Euston station in London.
It comes as more than 50,000 RMT members walked out, bringing the national rail network to a halt. London Underground workers are also striking on Tuesday.
Several professions could be about to follow rail workers in striking, including criminal defence barristers, teachers, NHS staff, junior doctors and care workers.
Asked if he had any advice to other unions considering strike action, Lynch told Sky News: “My advice to unions is to campaign on the issues.
“And, ultimately, if the government and the employers do not change their direction, I believe that more ballots for strike action are inevitable and more action is inevitable.
“What I would say to trade union leaders and trade union activists is we need to coordinate and synchronise our campaigning.
“So that we can rebalance the inequalities in our society. I think I’m knocking at an open door on that because the trade union leaders across the TUC and across Britain are telling me that they want to join this campaign.
“We had a massive rally on Saturday on these issues. Working people are crying out for leadership and direction.
“The Labour Party can contribute to that, but it’s going to be the trade unions that make the difference in this equation at the moment.”
Asked what he meant by “synchronising” Lynch replied: “We need to coordinate the action.
“So we need mass rallies, we need people on the streets, we need protests in every town and city in Britain and if we have to have industrial action, we should coordinate that industrial action so that it has the most effect possible.”
Transport secretary Grant Shapps vowed that ministers will change the law to minimise disruption from rail strikes by requiring a certain level of service to be run and enabling the use of agency workers.
He told Sky News: “We are going to ensure that the law is firmly on the passengers’ side.”
He added that the industrial action is “taking us back to the bad old days of union strikes” as he vowed to “push on” with reforms of the sector.
Last-ditch talks failed to resolve the bitter dispute over pay, jobs and conditions, with all sides blaming each other for the lack of progress. Strikes are also planned for Thursday and Saturday.