Redundancy notices have been sent to 400 staff at the Grangemouth refinery as owner Petroineos prepares to convert it to an import terminal. Only 65 of the roughly 500 jobs on the site will be required.

Sharon Graham, general secretary of trade union Unite, described the closure is a “national disgrace” and a “needless act of industrial vandalism”.

The union and community representatives have been involved in talks with the UK and Scottish Governments about an alternative plan which Ms Graham insists will give the plant a “clear path”.

She claimed Grangemouth could be used to produce sustainable aviation fuel.

“Just last week the UK Government announced the expansion of Heathrow and said that sustainable air fuel (SAF) will be needed. Well, Grangemouth can produce SAF – where is the joined up thinking?” she said.

“This the moment for the Government to lead and stand up to Petroineos in the national interest. Petroineos must allow the transition to SAF and biofuels.

A spokesman for Petroineos said: “From Q2 this year, Grangemouth will be ready to operate as a national fuel distribution hub that ensures Scotland’s supply of finished fuels is protected.

“The process of safely transitioning the site from a refinery into an import terminal is under way and will continue over a number of months.

“Fully winding down and dismantling the refinery is anticipated to take around five years in total, so the new terminal business will operate in parallel with this process.”

The union pointed to last week’s announcement by Rachel Reeves supportng Heathrow’s expansion that was directly linked to the introduction of SAF for UK flights.

“However, this was not linked to a plan to transition Grangemouth to SAF production, and the government will be unable to meet its own target of SAF production by 2030 without it,” said the union.

Gillian Mackay, the Scottish Green party MSP for Central Scotland, grew up just 200 yards from the refinery. She said: “This is a brutal blow for Scotland, but particularly for the community I grew up in and the workers who I know well.

“This is the opposite of the just transition that is needed for the site and for Grangemouth. We have known for a long time that change is needed.

“Our community has yet again been let down by both governments. Politicians of all parties need to step up and work with trade unions and the community to do everything they can to support local people.”

Scottish Conservative shadow energy and net zero secretary Douglas Lumsden said: “The loss of over 400 jobs at the refinery will be a hammer blow for the local economy, yet both SNP and Labour ministers have been missing in action.

“They have turned their backs on Scotland’s oil and gas industry and it is clear they want to accelerate its demise.”