Sir Keir Starmer has announced £200million of funding to help create a new industrial purpose for Grangemouth.
The prime minister made the pledge at Scottish Labour's conference in Glasgow ahead of the oil refinery, which is owned by Petroineos, closing in the summer with the loss of over 400 jobs.
It comes after First Minister John Swinney announced £25million of funding for the site earlier last week.
Aberdeen & Grampian Chamber of Commerce called on the Scottish Government to match the "Grangemouth urgency" in the North-east.
Starmer, the BBC reports, told the Scottish Labour conference: "We will grasp the opportunities at Grangemouth, work alongside partners to develop viable proposals, team up with business to get new industries off the ground.
"And to attract private investors into the partnership we need, we will allocate £200million from the National Wealth Fund, for investment in Grangemouth, investment in Scotland's industrial future."
Meanwhile at the conference, Scottish Labour leader Anas Sarwar promised to deliver the "biggest reform of the NHS in decades" should his party win the next Scottish election.
He vowed, the BBC reports, to counter a "growing culture of bureaucracy" by installing "fewer chief executives and more doctors".
Sarwar also detailed plans to introduce a Musk-style Department of Government Efficiency, a tax on online retailers, a ban on phones in classrooms and directly elected mayors for communities.