Determined Grangemouth refinery workers staged a vigil outside the shut down plant last night to remind owners Ineos they are standing firm against attacks on jobs, their union and a "vital national asset."

Members of the Unite union began to assemble as light faded yesterday evening and will keep it up until Monday, with a protest planned outside the huge plant on Sunday afternoon.

Unite convener Stephen Deans told the Morning Star: "This has turned from an opportunistic attack on me to an attack on our pay, pensions and jobs and an attempt to break the Unite union here at Grangemouth.

"They won't break the union - the members are absolutely solid."

Mr Deans called on both the Holyrood and Westminster governments to tell Ineos to end its attack on Scottish workers and the Grangemouth plant.

"We've had support from across Scotland - Labour MPs Mike Connarty and Jim Sheridan have been vocal in our defence, and Finance Secretary John Swinney has also been helpful and supportive."

Grangemouth remains closed after owners Ineos shut down operations following the setting of a strike date, which was then called off.

Ineos claims that it makes monthly losses of £10 million, putting the refinery's future in jeopardy.

However Unite says its own commissioned assessment of the firm's finances paints a different picture - and it has asked tax officials to take a closer look.

General secretary Len McCluskey has written to HM Revenue and Customs after last year's accounts revealed "a fundamental paradox," Mr McCluskey wrote, urging HMRC to "launch a formal investigation into the affairs of Ineos."

Mark Lyons, of the Unite shop stewards committee at Grangemouth, said: "We want a full inquiry into the financial affairs of Ineos and their backers."

And he was clear about the immediate goal: "We're asking the company to start the plant back up and end their attack on us - we want to get back to talks without a gun on the table."

Grangemouth lab technician Pauline Penman told the Star: "It's heartbreaking and unnecessary what the company are doing.

"But we're sticking together. The company has told a lot of lies, they keep on changing their story. But our union always tells the truth."