Demonstrators gathered in Westminster to hear speakers including deputy Labour leader Angela Rayner criticise the Government for failing to stop P&O from “disgracefully” sacking 800 workers.
Speeches from members of the Opposition and trade union leaders on Monday afternoon were met with applause and chants of “no to P&O” and “shame on you”.
Newly redundant seafarers in the crowd warned that the replacement of trained staff with cheaper agency workers would lead to a maritime “disaster”.
The Government could have done something about this some time ago and chose not to
Protesters had marched from the London offices of P&O to the Houses of Parliament waving signs reading “Stop the P&O jobs carve up”.
Addressing demonstrators as “comrades” near Parliament Square, Ms Rayner branded the treatment of workers “worse than the Victorian era” and called on the Government to take action.
“The Government could have done something about this some time ago and chose not to,” she said.
“We’ve got a Government that thinks getting rid of hard-working staff and employing agency workers on temporary contracts at £1.80 an hour is acceptable.
“Now it’s worse than the Victoria era. Well we say no. Again today the Labour Party has given the Government an opportunity to say what they mean and mean what they say and do something right for a change and look after the workers of this country.
“I know comrades, you’re going to win this fight.”
Labour will force an emergency vote in the Commons demanding that the Government takes action to outlaw the fire and rehire of staff, which involves making workers redundant before giving them their jobs back with worse terms and conditions.
Former shadow chancellor John McDonnell told the PA news agency he was “confident we will win this”, saying there was cross-party outrage at the company’s decision.
He branded the mass sackings “an absolute disgrace” and said DP World, the Dubai-based parent company of P&O, should not be allowed to operate in the UK unless workers are reinstated.
“I don’t think we should allow DP, as the company that owns P&O, to operate in this country at all, either on the freeports or on a lot of Government contracts, unless they reinstate these workers. We can’t tolerate this,” he said.
“We expect the Government to intervene to ensure all 800 workers are reinstated and that legislation is brought forward to prevent this ever happening again.”
The Rail, Maritime and Transport union (RMT), which represents many of the 800 fired staff, said their replacements are being paid well below the minimum wage in the UK.
General secretary Mick Lynch said: “The news that the seafarers now on ships in British ports are to be paid 2.38 dollars (£1.81) an hour is a shocking exploitation of those seafarers and another gut-wrenching betrayal of those who have been sacked.”
Hull East MP Karl Turner condemned P&O as a “disgusting, stinking, capitalist, predatory company”, and said he had spoken with devastated former workers including a man who was 18 months from retirement when he was sacked.
P&O Ferries said it had taken the “difficult decision” as a “last resort” and insisted the business would not have survived otherwise.
Mr Turner said: “(The Government) had the chance in the past and they’ve let the side down. It’s no good (Transport Secretary) Grant Shapps coming out now with his crocodile tears. He could do something to act today.
“A man I spoke to started as a deckhand at 17 years of age, he’s a first mate now. He’s got 18 months before he retires. (He was) crying like a baby to me about the disgust and the fact that he felt so betrayed by this disgusting, stinking, capitalist, predatory company.”
Lee Davison, 46, worked as a seaman for the company for 30 years before he was fired last week.
“I was a bit numb over the weekend, to be honest, but we’re back here today and I think everyone, myself and my colleagues, are angry now. We want something done about this,” he said.
He warned that potential “language barriers” caused by the hiring of overseas workers could lead to a dangerous “lack of transparency”.
“There’s going to be a disaster,” he said, adding that new agency workers were not to blame.
Referring to letters sent last week by Mr Shapps and Business Secretary Kwasi Kwarteng to P&O’s chief executive expressing their “anger and disappointment” at the move, Mr Davison said: “Strongly worded letters don’t get people their jobs back. We need action.
“Grown men were in tears because they don’t know what they’re going to do. This has had a terrible impact on people’s mental health. It’s shocking.
“If P&O get away with this, this will be a template for all employers across the country.”
