A probe into P&O Ferries' sacking of nearly 800 staff earlier this year has ruled out criminal proceedings - sparking anger from unions.

The Insolvency Service - part of the Department for Business, Energy and Industrial Strategy - was asked to investigate by Business Secretary Kwasi Kwarteng as to whether any offences had been committed.

In March, the cross-Channel ferry operator pulled all its vessels into port and sacked 786 staff - replacing them with cheaper agency staff.

It said at the time the move was necessary to protect the future of the company.

But following the probe, the Government agency said there was "no realistic prospect of a conviction".

A spokesperson said: “After a full and robust criminal investigation into the circumstances surrounding the employees who were made redundant by P&O Ferries, we have concluded that we will not commence criminal proceedings.”

A civil investigation is ongoing.

It comes just a day after DP World, the Dubai-based owners of P&O Ferries, announced record profits for the first half of 2022.

General secretary of maritime union Nautilus International, Mark Dickinson, said: "This is a deeply disappointing decision and will be met with frustration and anger by the 786 seafarers and their families who were so cruelly discarded by P&O Ferries.

“Only one day after P&O Ferries parent company announced record profits, making the company’s claims on operational sustainability questionable, we are further let down by a system that fails to punish apparent criminal corporatism.

“The message is clear, P&O Ferries must be held properly accountable for their disgraceful actions and we will continue the campaign to ensure that the CEO and his fellow directors are held to account and to make certain this can never happen again.”

During the hearings in Parliament, P&O's chief executive, Peter Hebblewaith admitted the firm had broken the law by not consulting with staff and unions prior to announcing to staff that there jobs would go.

A Government spokesman told the BBC: "In sacking 800 dedicated staff on the spot, P&O Ferries not only acted callously but failed to uphold the high standards we expect of British businesses.

“Given their appalling behaviour, it’s very disappointing that the company will not face criminal proceedings.”

Sailings were suspended for weeks following the P&O decision to sack its staff - causing chaos on Kent's roads during the busy Easter holiday period.