Britain could be brought by a standstill by a wave of strikes hitting "every sector of the economy", a union chief warned this morning.
Mick Lynch, general secretary of the Rail, Maritime and Transport union (RMT), joined striking rail workers at Euston Station taking part in a picket line.
Just one in five trains are running across the country because of the mass walkout by members of the RMT and TSSA unions.
He warned that industrial action is likely to spread across industries in the coming months, saying people "are fed up with the way they've been treated".
But Mr Lynch stopped short of predicting a General Strike, saying that could only be done by the TUC.
Mr Lynch said: "What you are going to get is a wave of solidarity action, generalised strike action, synchronised action.
"And you'll see it in every sector of the economy, in education, in health, wider parts of the transport system, in all sectors, the private sector as well.
"People are fed up with the way they've been treated. The British worker is basically underpaid and gets no dignity or respect in the workplace.
"We've got to change that so we get a square deal for everyone in Britain - and that's what the unions are determined to do."
He said the rail strike "won't be broken" until there is a settlement to the dispute as he refused to put an end date on the industrial action.
Speaking in front of a picket line at Euston station, the RMT general secretary told the PA news agency: "We don't have a fixed programme - I don't have a whiteboard saying it starts on this day and it ends on that day.
"We won't be broken. We are determined to get a settlement.
"People have shown on the picket lines they are determined to dig in, we're not going to waste our members' efforts.
"We will take the action that our members want to take as we go along, so we're not going to be broken.
"We will continue the fight until we get a settlement."
A Department for Transport spokesperson said: "Yet again, for the sixth time since June, union leaders are opting to inflict misery and disrupt the day-to-day lives of millions instead of working with industry to agree a deal that will bring our railways into the 21st century.
"Today, thousands of A-level students across the country, many of whom have spent the majority of their college years studying at home due to the pandemic, are now being denied the chance to celebrate their hard work and dedication face to face with peers and teachers.
"It's clear strikes are not the powerful tool they once were and union chiefs are no longer able to bring the country to a standstill as, unlike them, the world has changed and people simply work from home.
"All these strikes are doing is hurting those people the unions claim to represent, many of whom will again be out of pocket and forced to miss a day's work.
"We urge union bosses to do the right thing by their members and let them have their say on Network Rail's very fair deal, which will deliver the reforms our rail system urgently needs.
"It's time to get off the picket lines and back around the negotiating table - the future of our railway depends on it."
