Extra supplies of fuel are being shipped to Scotland as a strike by workers at the Grangemouth oil refinery enters its second day.

Around 65,000 tonnes of fuel, mostly diesel, are being shipped in from Europe in seven tankers to ease pressure on the forecourts.

Two tankers have been making their way up the River Forth, while the remaining five were destined to arrive in Scotland over the next couple of days.

Included in the convoy are four major shipments from Rotterdam, Amsterdam and Gothenburg.

Another tanker, carrying 3,000 tonnes of diesel and kerosene from Grangemouth, arrived at Aberdeen Sunday evening, although fog was preventing it from coming in to port.

News of the strike has had an impact on the availability of petrol and diesel in Scotland, leaving some of Scotland's 956 filling station forecourts short as motorists rushed to fill up their tanks.

The Scottish Government said that at midday on Saturday, five filling stations were out of fuel and 70 had partially run out.

But it stressed that essential services, including emergency vehicles, will receive the fuel they need to continue to operate.

Staff at the Grangemouth plant began their 48-hour walkout at 6am on Sunday and held a mass rally in their dispute with operators Ineos over proposed changes to pensions.

The plant has been shut down along with a major BP pipeline which is powered by the site.

Grangemouth oil workers have taken out a series of adverts in the Scottish media to explain the reasons for their strike and to ask for the public's understanding and support.

Unite national officer, Phil McNulty said a lot of "untruths" had been peddled about the reason for the walkout.

He said: "Our members have been accused of being greedy and irresponsible but this strike is not about getting more money from their employer or an attack on the ordinary people of Scotland.

"The Grangemouth workers are having to strike to defend their existing pension scheme which, despite the fact it is well-funded and in profit, their hugely rich employer, Ineos, wants to close."

But Tom Crotty, chief executive of Ineos, claimed the company had made a number of concessions to the union.

"We have been working on a nine-month process. Six months into that the union have stood up, thrown a strike on the table and walked away from those talks," he said.

Industry representative Oil and Gas UK has called for ministers to intervene, saying around 80 companies were caught up in a situation which has nothing to do with them.

First Minister Alex Salmond, who is expected to discuss the issue with Prime Minister Gordon Brown in person at some point, said the two parties now had to engage in discussions to resolve the dispute as quickly as possible.

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