LABOUR has refused to back a potential strike by airport staff belonging to unions who are among the party’s biggest funders.

Shadow Foreign Secretary David Lammy gave a “categorical no” to strike action by around BA check-in staff at London's Heathrow Airport balloted by Unite and the GMB. 

He also criticised Labour MPs who joined picket lines during last week’s rail strikes by members of the RMT union, which is not affiliated to Labour.

“A serious party of government does not join picket lines,” he told the BBC.

He denied Sir Keir Starmer had “lost control” of around 50 MPs who defied the party’s instruction not to join pickets. Scottish Labour leader Anas Sawar also joined rail strikers last week.

“I suspect the chief whip will be speaking to them next week and making it very clear that a serious party of government does not join picket lines,” Mr Lammy said.

The Tottenham MP said Labour continued to support negotiations in disputes over pay, jobs and working conditions rather than industrial action.

Asked if he would support BA staff who are being balloted by the GMB and Unite unions to strike, Mr Lammy told BBC News on Sunday: “All of us are feeling the pinch with inflation.

“Many of us might want a (pay) rise of 10%; in truth, most people understand it’s unlikely that you’re going to get that. It absolutely would not be right, it would not be responsible opposition, if I suggested yes to every strike.”

Pressed on whether he supports the proposed strike by check-in staff, he said: “No, I don’t. No, I don’t – it is a no, it’s a categorical no.”

“Because I’m serious about the business of being in government and the business of being in government is that you support negotiation.”

Mr Lammy argued Labour supports all working people, including those who need to travel by train to make a living.

“Let’s take these rail strikes - working people find it very hard when they can’t get to work to make a living, but equally there are working people who work on the railways who are seeing their pay diminished and have concerns about redundancies at this time.

“The way to deal with that is through negotiation, getting around the table.”

He later said: “We have just seen that the parties that have lost control are parties that lose votes, and I think that’s the Conservatives and the Prime Minister who’s lost his backbenchers. The Labour Party is in a strong position with strong leadership and a clear direction of travel.”

He denied Labour was split over whether to back strike action in the face of double–digit inflation and a cost of living crisis.

Communication Workers Union general secretary Dave Ward said Labour had “miscalculated” their approach to this summer’s strike action.

He told Sky News: “It’s up to Keir Starmer what he does, but what we’re going to do is chat to working people across the UK, in communities coming together to really bring about serious change.”