UK Transport Secretary Grant Shapps urged Britons to boycott P&O Ferries after it sacked crews without consultation and said the company will ultimately be forced to reverse the measures.

“They are going to have to u-turn,” Shapps said Thursday in an interview with Bloomberg News. “The sooner they get on with doing it the better, because there is no future in the model that they’re running.”

People traveling to continental Europe should explore alternatives to P&O including rival ferry firms, flights and train services through the Channel Tunnel, Shapps said by phone.

P&O is meanwhile under investigation for “both civil and criminal actions,” the minister said. Chief Executive Officer Peter Hebblethwaite previously inflamed legislators by telling them the firm had made a conscious decision to break the rules knowing staff wouldn’t go along with the restructuring plans.

Shapps pledged that P&O won’t get away with the firings, which the unit of Dubai-based DP World has sought to justify as essential to avoid collapse. Measures confirmed last week in the legislative agenda for the new parliament will ensure that the company needs to change tack, he said.

“They will have no choice because the law is going to be changed,” said Shapps. A rethink from P&O is also inevitable given the “terrible publicity” surrounding the sackings and “because the British people will demand it,” he said.

Shapps revealed that government departments have in the past week carried out extensive checks for contracts with P&O and that one remaining arrangement with the Border Force agency, which polices U.K. entry points, has been scrapped.

The minister said the harbor authorities that will be legally required to check ferry firms are paying the UK minimum wage are perfectly capable of fulfilling that role, just as they carry out insurance checks, and that he recently had conversations with owners including Associated British Ports on the matter.

“It’s not unreasonable, and indeed pretty straightforward to ask the operator of a ship to confirm that they’re paying the minimum wage if they’re plying a regular route,” Shapps said.

At the same time, the Department for Transport, the Maritime and Coastguard Agency and HM Revenue & Customs will retain ultimate responsibility for enforcement. “We are not asking the ports to police that,” he said. “All we’re asking them to do is have received confirmation.”

P&O sparked an uproar in March when it fired 800 seafarers, many by video call. Shapps said that eight other steps aimed at tightening maritime employment rules in response to the move don’t require legislation and are proceeding.