Tory MP Huw Merriman said the issue was “deeply concerning” and urged the government “to do everything it can to ensure that this appalling employment transaction cannot be completed”.

He added: “Concern remains as to whether this is lawful. Firing loyal staff and replacing them with cheaper labour sourced from elsewhere is not a model that the public will wear.”

Merriman recalled a similar tactic by British Airways during lockdown, when, according to union Unite, BA made 4,700 cabin crew redundant. Those that remained were forced to accept pay cuts and demotions which meant salaries fell between 15 and 35%.

“That model was not acceptable when our national flag carrier airline attempted to adopt it, and it is not acceptable now,” he said.

“The government should make it clear that it will not condone this behaviour. P&O’s parent company, DP World, must understand that British customers won’t do business with companies that treat their staff with contempt.”