The Labour MP said the closure was a “Scotland-wide issue”, adding: “We saw, with the closure of the refinery, over £400m disappear out of Scotland’s economy.
“There’s going to be a huge implication for Scotland’s economy with Syngenta closing.”
He urged the prime minister to “do the right thing” and save the site, similar to how the UK government saved British Steel.
“We’re talking about 377 jobs on site – we will be talking about thousands of jobs in the wider supply chain,” said Leishman.
“A huge piece of Scotland’s manufacturing base. Scotland deserves better.”
Reindustrialisation Minister Blair McDougall said the UK government would continue to work closely with Syngenta to explore all options for the site and the workforce.
He said: “I know this will be a deeply concerning time for workers at Syngenta and their families, and I met with the company yesterday to discuss all options for the site and the workforce.
“We worked closely with Syngenta and the Scottish government to explore every possible avenue to support them, but the company has now made this commercial decision.
“We remain committed to supporting jobs in Grangemouth following the hundreds we have already protected, and will work urgently with the National Wealth Fund in the next few days to explore all options for the area.”
