The company added that it would keep the pipeline open as long as possible, but anticipated shutting it late on Saturday, if strike action went ahead.
Safety issues mean the pipeline requires between 12 and 24 hours to reopen.
Malcolm Webb, chief executive of oil and gas industry body, Oil and Gas UK, warned the impact of the dispute could be considerable.
He said: "This potential loss of production would have a wholly disproportionate effect on the national economy, losing the UK about £50m every day, of which foregone tax revenue to the Exchequer amounts to £25m a day.
"Moreover, if oil and gas production offshore were to be shut down, re-starting cannot happen at the flick of a switch. It would take several days to restart safely."
Oil economist Professor Alex Kemp, of Aberdeen University, said: "We are talking about 700,000 barrels a day, which is a very high proportion of the total UK production.
"When you consider that the price of a barrel of oil is currently about $110 you can see that it will be a major loss of revenue."
The UK's energy minister Malcolm Wicks described the pipeline as a "crucial" piece of infrastructure.
Truckers on the impact of the refinery shutdown
Speaking to the BBC, the minister warned the public against panic buying but admitted there were "logistical" problems getting fuel to some forecourts.
He said: "This is not a supply issue, it is a logistical issue and the industry is responding well."
There have been reports across Scotland of fuel running out, rationing, queues, and price hikes.
Emergency planning groups are convening to assess the impact of any shortages.
There was not said to be any sign of increased fuel buying in the north of England or Northern Ireland.
The dispute has prompted concern from business groups who rely on undisrupted fuel access.
The Freight Transport Association, which represents the transport interests of companies moving goods by road, rail, sea and air, called on ministers to ensure diesel supplies.
Geoff Dossetter, the organisation's external affairs spokesman said: "Malcolm Wicks said that although there was plenty of fuel available, there could be problems with the logistics required to get it to the right places where it will be required.
"As such it makes sense to here and now plan for the possibility of a problem rather than put our trust in hopes that it will not be required."
A further meeting has taken place between the Grangemouth plant's operators Ineos and representatives from the Unite trade union in a last ditch effort to avert the strike.
The meeting was called primarily to discuss safety matters at the plant, although the broader issues involved in the dispute will be discussed, the BBC understands.
Two days of talks at conciliation service Acas in London earlier this week failed to resolve the dispute.
Unite had warned that the strike could be escalated after talks between the two sides broke down on Wednesday.
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