Workers at Scotland's largest refinery have walked out a road in a dispute over pay on Wednesday. 

They swarmed the A904 in Grangemouth in the early hours of the morning before blocking the road outside the INEOS office. 

It is understood around 100 maintenance workers joined the unofficial picket outside the Grangemouth refinery and petrochemical plant as part of a nationwide protest. 

The action comes in response to a dispute with the Engineering Construction Industry Association (ECIA) - as contractors urge it to open pay negotiations. 

A pamphlet handed out to members of the public claimed the association has refused "to recognise the impact of the cost of living crisis."

It added that a 2.5% pay increase scheduled for next January would give the workers "real terms pay cut of at least 10%" amid skyrocketing inflation. 

"Many employers have acknowledged these events and have negotiated pay rises and one-off payments for the struggling workforce," it read.

"Unfortunately, workers covered by the NAECI and those whose pay mirrors the NAECI are expected to just get on with it."

Adding that workers accepted changes to the agreement during the pandemic and even took a "pay freeze to help the employers", the pamphlet urged for new negotiations.  

"Now we are asking for the ECIA to come back to the negotiating table because of these once in a lifetime events, which have caused spiralling inflation. 

"So far, they have point blank refused. We cannot allow this cavalier attitude to continue."

INEOS said their manufacturing and fuel distribution operations are not affected by the wildcat strike. 

The Grangemouth refinery provides two-thirds of the petrol and diesel used by Scottish forecourts.

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Police Scotland officers are at the scene and confirmed closures from Inchyra Road to Boness Road.

An INEOS spokesperson said: "We can confirm that a number of contractors, employed by third parties are taking unofficial industrial action at the INEOS Grangemouth site as part of a nationwide protest event.

"Our manufacturing and fuel distribution operations are unaffected.

"The site has a very good working relationship with the contracting companies and their employees at Grangemouth including those operating under the NAECI agreement.

"We are disappointed that the protestors have chosen to use the INEOS Grangemouth site as one of their backdrops for their unofficial action today."

ECIA has been approached for comment.