Sir Keir Starmer has backed calls for British Airways to lose some of its lucrative Heathrow slots over the treatment of its workforce.

The Labour leader claimed there should be consequences for the airline’s actions and urged Boris Johnson to intervene.

British Airways is proposing to cut up to 12,000 jobs due to the collapse in demand caused by the coronavirus pandemic.

The airline has insisted its proposals have been put forward with a view to consultation, adding that no decisions have been taken with regard to actual redundancies.

Trade union Unite has accused the company of planning a “fire and rehire” system which will involve remaining employees having their terms and conditions downgraded.

Slots – which give an airline the right to take off and land at an airport – can be worth several million pounds at Heathrow, where British Airways holds the majority.

They are generally allocated to incumbent airlines, but last week more than 100 MPs backed calls for the rules to be amended in response to the airline’s actions.

At Prime Minister’s Questions, Sir Keir said: “Alongside the 12,000 redundancies already announced, BA is trying to force through the rehiring of the remaining 30,000 workers on worse terms and conditions.

“That is totally unacceptable and it is a warning shot to many other working people.”

He added: “Will the Prime Minister now personally intervene and make clear that actions like those at BA cannot be allowed to stand without consequences for landing slots?”

Mr Johnson said: “Let’s be absolutely clear, British Airways and many other companies are in severe difficulties at the moment and we cannot, I’m afraid, simply with a magic wand ensure that every single job that was being done before the crisis is retained after the crisis.

“What we can do and what we are doing is encouraging companies to keep their workers on with the Job Retention Scheme, with the Job Retention Bonus and with a massive programme in investing in this country, a £600 million investment programme in this country to build, build, build and create jobs, jobs, jobs.”

British Airways said in a statement: “For more than a century British Airways has been connecting Britain with the world, but today as the world remains largely closed, the airline is facing its biggest ever challenge.

“It is disappointing for a company taking action to save as many jobs as possible to be singled out in this way.

“Politicians should be wary of supporting a union campaign that would ultimately result in the loss of more British jobs.

“Instead of acting against us, Unite and GMB need to consult with us on our proposals as our pilot union, Balpa, is doing.

“Working together we can protect more jobs as we prepare for a new future.”

In a recent letter to staff, British Airways chief executive Alex Cruz wrote that “every slot lost will lead to jobs in BA being permanently lost”.