UK ports will get new powers to block ferries from docking if they do not pay their crew the minimum wage.
Transport Secretary Grant Shapps said the move was a warning to P&O Ferries - after the firm's no-notice sackings of 800 staff to replace them with cheaper agency workers - that "the game is up".
"This will send a clear message to the maritime industry: we will not allow this to happen again," he told the Commons.
But the plans have already been criticised, with unions saying ministers have not gone far enough and the British Ports Association pointing out ports cannot enforce wage rules.
Mr Shapps also outlined plans to close minimum wage loopholes and clampdown on fire and rehire practices.
He will ask the Insolvency Service to consider disqualifying P&O chief executive Peter Hebblethwaite from acting as a company director, after the boss brazenly admitted to MPs the firm broke the law by not consulting with unions or notifying the government.
TUC general secretary Frances O’Grady said: “This plan has gaping holes. It won’t deliver a fair outcome for the 800 sacked workers, and it won’t stop another P&O-style scandal.
“Closing the legal loophole which lets companies pay less than the minimum wage is a start, but we need much more from the Government.
“Ministers must do everything they can to ensure P&O reinstate staff on their previous pay – a union-negotiated rate that is significantly higher than the national minimum wage.
“That means severing all ties with DP World, including lucrative freeport contracts.
“And if ministers really want to stop companies firing at will, they must go further than a feeble statutory code and finally deliver the long-promised Employment Bill to boost worker protections.
“Without stronger employment legislation, bad bosses will continue to trample over workers’ rights.”
British Ports Association, Richard Ballantyne, added: "While it's right the government and the ferry industry look to improve employment rules and standards, the expectation that port authorities will need to enforce minimum wage rules in the shipping sector could be unworkable.
"This will place ports in a difficult legal predicament, especially before any legislation is in place."
DP World-owned P&O Ferries sacked its crews and replaced them with agency workers on March 17.
The minimum wage in the UK for people aged 23 and over is £8.91 per hour.
Mr Hebblethwaite, whose basic annual salary is £325,000, told MPs on March 24 that the average pay of the agency crew is £5.50 per hour, but insisted this was permitted under international maritime laws.
Speaking in the Commons, Mr Shapps said: “Where new laws are needed, we will create them. Where legal loopholes are cynically exploited, we will close them. And where employment rights are too weak, we will strengthen them.”
Mr Shapps said HM Revenue & Customs will dedicate “significant resource” to ensure all UK ferry operators are “compliant with the national minimum wage, no ifs, no buts”.
Employers will be prevented from using “ fire and rehire tactics” if they fail to make “reasonable efforts to reach agreement through consultation”, the Transport Secretary said.
Mr Shapps added of the proposals: “It’ll send a clear message that if you are using British waters and British ports to ply your trade then you must accept British laws.”
Shadow transport secretary Louise Haigh told the Commons that the steps announced by the Government to “insist on the bare minimum cannot come a moment too soon”.
P&O Ferries has accused the Maritime and Coastguard Agency (MCA) of operating with “an unprecedented level of rigour” after it detained two of its ships.
European Causeway was held in Larne, Northern Ireland, on Friday, while Pride Of Kent was detained in Dover, Kent, on Monday.
Mick Lynch, general secretary of the Rail, Maritime and Transport union, was also unimpressed with the plans, saying: “Despite all the bluster, Grant Shapps has failed to grasp the opportunity to adequately stand up to the banditry behaviour of P&O.
“The Prime Minister repeatedly said to Parliament that the Government would be taking legal action to save British seafarers’ jobs, but he has failed to keep his word.
“This continued lack of action and courage has meant a ferry company owned by the Dubai royal family has been able to break our laws and disrupt our ports and ruin people’s lives with impunity, and we will keep pressing the Government to ensure justice for our members.
“What has been announced today is far too little, too late, and we are calling for urgent action for speedier, more radical reforms to save the UK seafarer from oblivion.”
