The No 10 hopeful has pledged to ensure “militant action” from trade unions can no longer “paralyse” the economy if she replaces outgoing Tory leader Boris Johnson.
Mick Lynch, general secretary of the Rail, Maritime and Transport (RMT) union, said “coordinated and synchronised industrial action” would be needed if legislation is brought in. He said the “very dangerous situation” risks taking the country back to “Victorian times”.
Mr Lynch’s remarks came as strikes by members of the RMT and Transport Salaried Staffs Association left only around one in five trains running, bringing the country to a grinding halt.
In the wake of Wednesday’s stike action, Aslef - the train drivers’ union - announced its members will walk out on Saturday 13 August, citing the failure of train firms to make a pay offer to help members keep pace with the rising cost of living as the trigger.
Mr Lynch told the i newspaper: “There is a whole host of measures that [Ms Truss] is looking to bring in that will make it virtually impossible to have effective trade unionism and we think would effectively outlaw collective action.
“I think that’s a turn to the extreme right on behalf of the Conservatives, and they’re playing to their reactionary base. I think there will be an enormous response from the trade union movement.”
He contined: “I would be looking for a general strike if we can bring that off, but it’s up to others. We’re a small union compared to others. So we’ll have to see where that goes.”
Ms Truss has said her government would introduce legislation in the first 30 days of parliament to guarantee a minimum level of service on vital national infrastructure.
She vowed she would also ensure strike action has significant support from union members by raising the minimum threshold for voting in favour of strike action from 40 per cent to 50 per cent. The minimum notice period for strike action would be raised from two weeks to four weeks, and a cooling-off period would be implemented so that unions can no longer strike as many times as they like in the six-month period after a ballot.
Asked what she would do about the rail strikes, the foreign secretary told Sky News: "I would legislate to make sure that there are essential services on our railway.
"It is completely wrong that the travelling public are being held ransom by militant unions. We can't allow that to happen. We need to make sure our essential services run.
"As I said, I am on the side of people who work hard, who go into work, who want to run their businesses. We can't see them hampered by the activities of these militant unions."
A general strike, which can only be called by the Trades Union Congress (TUC), is when a “substantial proportion” of workers in multiple sectors refuse to work until their demands are met.
And asked if it would call a general strike, the TUC stressed “every strike is a democratic process”, but said: “It’s clear this Conservative government is not on the side of working people.”
It follows the war of words which erupted on Wednesday between unions and transport secretary Grant Shapps after he laid out plans to curb industrial action, including stopping coordinated industrial walk outs, limiting picketing and having a cooling off period after strikes.
He told the Daily Telegraph: “I’m looking at banning strikes by different unions in the same workplace within a set period. We should also place an absolute limit of six pickets at points of Critical National Infrastructure, irrespective of the number of unions involved, and outlaw intimidatory language.
“Ballot papers should also set out clearly the specific reason for industrial action and the form of action to be taken. In addition, before strike dates are announced, employers should have the right to respond to the issue cited on the ballot paper.”
Echoing comments made by Mr Lynch, Unite general secretary Sharon Graham said: “If Grant Shapps had his way we would all still be in the workhouse.”
Unison general secretary Christina McAnea added: “The government wants to turn the clock back to Victorian times when children were sent up chimneys and working people ruthlessly exploited.”
Meanwhile, Sam Tarry has warned that the Labour leadership is on a “direct collision course” with trade union chiefs who have been left “absolutely fuming” by his sacking from the party frontbench for joining a rail strike picket line.
The former junior shadow transport minister attended a demonstration at Euston Station in London - defying Sir Keir Starmer’s order to stay away from rail worker demonstrations.
The Labour leader warned his party’s shadow ministers on Tuesday not to join picket lines on a one-day walkout by RMT members seeking a better pay offer.
A Labour spokesperson said: “This isn’t about appearing on a picket line. Members of the front bench sign up to collective responsibility. That includes media appearances being approved and speaking to agreed frontbench positions.
“As a government-in-waiting, any breach of collective responsibility is taken extremely seriously and for these reasons Sam Tarry has been removed from the frontbench.”
But responding to the news of Mr Tarry’s sacking, TSSA general secretary Manuel Cortes said: “Sam is one of us. He grew up in the trade union movement and trade unionism is in his blood. Today Sam did the right thing and stood shoulder to shoulder with rail workers striking for fairness and safety at work.
“Whatever excuses the Labour party makes about the reasons for Sam being sacked, the reality is that Sam has shown solidarity with his class and we applaud him for that. The Labour party needs to wake up and smell the coffee. If they think can win the next general election while pushing away seven million trade union members, they are deluded.”
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