One of the UK’s top union bosses says the owner of P&O Ferries has got off “scot-free” for firing 800 workers after the firm reported record profits on Thursday.

DP World said that it had made a profit of 884 million dollars (£736 million) over the six months to the end of June.

It was an increase of more than 51% over the year as the business said it had focused on shipping cargo with higher profit margins.

“We are delighted to report a record set of first half results,” said chair and chief executive Sultan Ahmed Bin Sulayem.

“This significant growth demonstrates that our strategy to focus on high margin cargo and to offer customised supply chain solutions will provide sustainable returns in the long term.”

Frances O’Grady, the secretary general of the Trades Union Congress, called on the Government to scrap all its contracts with DP World.

“DP World have been allowed to get away scot-free with behaving like corporate gangsters,” she said.

“These eye-watering profits have come off the back of P&O illegally sacking hundreds of dedicated staff. They are an insult to common decency.

“Ministers should have stripped DP world of all their lucrative public contracts and severed all commercial ties with the company.

“But now they too are using the P&O playbook.

“Having slammed P&O for replacing experienced workers with agency staff, Grant Shapps has passed laws that will allow employers to bus in agency workers during strikes.

“At a time when the cost of living is soaring and wages are falling, the Conservative government wants to make it much harder for people to win better pay and conditions.”

P&O Ferries sparked public anger and was hauled in front of MPs to answer questions when it sacked hundreds of workers without notice in March.

During the hearings in Parliament the business admitted that it had broken the law that would have forced them to give notice of the firings. This was because no unions would have accepted its new proposals, bosses said at the time.