The closure of Grangemouth oil refinery will “compromise” Scotland’s national security, a Labour MP has said.

Brian Leishman said the thousands of jobs that would be lost at the refinery and in its supply chain will have a devastating effect on the area.

Under current proposals PetroIneos, which owns the site on the banks of the Forth of Firth, will convert it into a import terminal to bring finished petrol, diesel, aviation fuel and kerosene into Scotland. A consultation is under way on the potential closure next year.

Speaking during the debate on the Great British Energy Bill, Mr Leishman, Labour MP for Alloa and Grangemouth, welcomed the legislation. However, he said it was at odds with the proposed closure of the refinery.

He said: “I have heard it said, indeed I have said, that a nation’s energy security is linked to its national security, and GB Energy should eventually help with both of these things. And of course, it was said that GB Energy will create thousands of highly skilled jobs. That is excellent.

“However, what about the jobs of the Grangemouth refinery workers? The same workers who are right now crucial to Scotland’s energy security, and therefore Scotland’s national security. Those workers are nearing the end of their 45-day consultation process in which the focus should be on how jobs can be saved and maintained for those workers.

“Recent comments like, ‘these workers will be OK’, and ‘it will all be fine because they will get employment elsewhere’. That doesn’t help my community if the workers need to leave. It does not help Scotland’s fuel and national security if refining stops.

“There can be no doubting that my constituency will be weaker for losing the refinery. Job losses will run into the thousands. There can be no doubt that Scotland will be weaker for losing their refinery.”

Unite the union, which represents workers at Grangemouth, has previously called its proposed closure a “horrific act of industrial vandalism”. Union bosses have called for the plant to be kept open while low carbon and renewables projects are sped up to ensure there is no gap in employment for workers.

Last month, general secretary Sharon Graham told a Unite policy conference in Dundee: “Labour must be forced to act. Grangemouth is making net zero look far from a just transition, more a jobless transition.”

The consultation on Grangemouth comes amid the Finnart oil terminal’s closure in west Scotland. The two are connected by pipeline, with Finnart also due to close next year.

Mr Leishman said: “Mark my words, stopping refining at Grangemouth and the closure of Finnart will have monumental consequences for all of Scotland. It won’t take long for the pumps on forecourts all over the country to be impacted, and that means so will the public.”

He added: “If the refinery closes, then jobs will be lost, communities will be impoverished and Scotland’s fuel and national security will absolutely be compromised.

“There are economic, social and moral reasons to keep Grangemouth working, and if they are not enough, and they really should be, then let me say that there is also a political reason, because you will be judged at the ballot box on what happens next. And not just in the 2026 Scottish parliament election.

“Let me say it’s not too late for the Government to do the right thing. Speak with Unite the union, listen to what they say, engage and negotiate with Ineos to deliver a proper and true just transition and to keep Grangemouth working until the new industrial cluster is ready at the site.”