Image caption Alex Salmond held talks with Len McCluskey of Unite over the future of Grangemouth

First Minister Alex Salmond has said he is "absolutely certain" that the petrochemical plant at Grangemouth can be saved.

Staff are waiting to hear if owner Ineos will grant a reprieve to the closure-threatened operation.

About 800 jobs are under threat - and the company has already laid off about 2,000 contractors since it shut down the complex.

Ineos will update the staff on its plans at a meeting at 11:00.

Speaking on the BBC Radio's Good Morning Scotland programme, Mr Salmond said: "I would now be very hopeful indeed that there will be a change in position from Ineos and I'm absolutely certain there's a future for chemicals in Grangemouth.

"I believe there will be a change in position today and that will be a favourable change in position.

"My reason for saying that is that everybody has been going that extra mile I called for.

"Given that only 48 hours ago we were looking at a major industrial catastrophe in Scotland, I think we're in a much better position this Friday morning."

Mr Salmond said the trade unions had offered that there would be no industrial action for three years.

Background: Grangemouth dispute The dispute first flared up in the summer over the company's treatment of Unite official Stephen Deans, who has worked at Grangemouth for more than 20 years

He was accused of trying to rig the selection of a Labour candidate for the Falkirk seat at Westminster but was later cleared

But Ineos has been carrying out its own investigation into claims Mr Deans improperly used the refinery for union business. Its findings are due to be published on Friday

Unite members at Grangemouth had been due to strike last Sunday over Mr Dean's treatment

Ineos had closed the plant ahead of the industrial action and said it would not be restarting the facility even after the strike was called off

It said Grangemouth was losing huge amounts of money and faced going bust unless staff agreed to a survival plan

The proposals included changes to pay and conditions. They were rejected by about half of the site's workers

The decision that the petrochemical plant should close was taken at a meeting of Ineos shareholders, including chairman and founder Jim Ratcliffe, on Tuesday

On Wednesday, the plant's workforce was told of the closure, with Unite describing the move as "catastrophic"

Hopes for the site's future were raised on Thursday after Unite agreed to "embrace" a survival plan put forward by Ineos management Why Grangemouth matters Grangemouth dispute: The key players

"That's an indication that however we got to this impasse two days ago, there has now been substantial movement of people anxious to save their jobs, their livelihoods and their plants," he told the programme.

Political leaders had already expressed optimism after the union accepted a survival plan put forward by Ineos.

The BBC understands that an agreement was being drawn up for workers to sign, which would need approval from major Ineos shareholder Jim Ratcliffe.

On Thursday, Scotland's finance secretary John Swinney and the Scottish Secretary Alastair Carmichael held talks with unions and management at the site. Afterwards they said they were hopeful.

However, Ineos is yet to confirm whether it will reverse its decision to close the petrochemical plant at the complex.

An internal investigation by Ineos into the union convenor, Stephen Deans, is also due to be published later.

It was the firm's treatment of Mr Deans that first ignited the breakdown in industrial relations - before it became a battle for the survival of Scotland's largest industrial site.

The dispute at the site escalated to the threat of strike action.

This was dropped but Ineos shut down the plant and issued an offer of revised terms and conditions in a survival plan, which was initially rejected by union members.

The proposals included ending their final salary pension scheme and cut shift allowances.

Previously, Ineos said it was ready to invest £300m in Grangemouth if workers agreed to the new terms and conditions.

The company said it had decided to close the plant because half the workforce had refused to accept the cost-cutting plan essential for the facility's survival.

Ineos chairman and founder Jim Ratcliffe had said at the weekend that if the petrochemical plant closed it was likely the neighbouring refinery would go as well.

The refinery provides most of the fuel to Scotland, the north of England and Northern Ireland.

Ineos had said liquidators for the petrochemical plant would be appointed within a week.