The opposition have asked if there are any legal steps ministers could take to reverse the decision to sack so many staff without consultation
Labor is urging the government to publish the legal advice it has received on whether P&O broke the law by sacking 800 workers.
The opposition asked if there were any legal steps ministers could take to reverse the decision to sack so many staff without consultation.
He also published an analysis of the data which he says shows P&O Ferries has received £38.3million in government contracts since December 2018.
Protesters are due to march on the Conservative Party Conference on Saturday for another day of demonstrations against the movement.
Protesters will gather at the Comedy Carpet near Blackpool Tower on Saturday as speakers including Prime Minister Boris Johnson and Home Secretary Priti Patel are due to address the forum.
Labor leader Sir Keir Starmer has also called on the government to suspend contracts with the ferry giant and its owners DP World until the situation is resolved.
Sir Keir said: “The actions of P&O are aggressive and immoral. The government’s apparent inaction is as telling of its respect for workplace safety as it is damning.
He added: “This Conservative government bears the responsibility. Boris Johnson’s party has created an environment in which big business thinks it has the right to disregard good employment practice, fundamental respect for workers and everyone’s right to be treated fairly.
“If a company can offload responsibility for its workforce and the government doesn’t blink, others have the opportunity to do the same.
“We ask the Prime Minister to access the legal advice the Department for Transport has received on whether P&O Ferry’s actions constitute a breach of the law and whether there are legal levers to overturn the decision.
“Full transparency is essential to prevent anyone from being subjected to this appalling behavior. Any government contracts they have should be suspended until this is resolved.
On Friday, Transport Secretary Grant Shapps and Business Secretary Kwasi Kwarteng wrote to the chief executive of P&O to express their “disappointment and anger” at the massive sacking.
Mr Shapps said he had instructed the Maritime and Coast Guard Agency (MCA) to carry out inspections of all P&O vessels before they return to sea to check that the new crews the company has precipitated” are safe.
P&O crisis sparks safety fears as operator replaces seafarers with temps
He urged the company to change course and said the government was “carefully reviewing” its relationship with P&O and its parent company, DP World.
Demonstrations took place in the ports of London, Liverpool, Larne, Hull and Dover on Friday as unions called for a boycott of the company.
TUC general secretary Frances O’Grady said: “We need to get to the bottom of this scandal.
“The government must be transparent and publish the legal opinions it has received. It’s the least the P&O crew deserves.
“If the company has broken the law, it must face serious consequences – not just a slap on the wrist.
“What happened at P&O can never happen again.
“Ministers must urgently introduce a Jobs Bill to stop workers being treated as disposable labour. The time for excuses is over.