A potential rescue package for the Hall's of Broxburn plant, which processes 71% of Scottish pig meat and employs 1,700 people, was rejected last week by owners Vion UK.
Proposals were put forward by a taskforce, which comprises Scottish finance secretary John Swinney, West Lothian Council, Scottish Enterprise and other partners, for the site to be bought and leased back to the company, but these were rejected.
A Vion spokesman said: "Given the scale of the losses at Hall's of £79,000 a day and the complexity and inefficient layout of the factory, we regret that we are unable to accept this support.
"It would be wrong to accept the offer of public money knowing it is significantly below the amount required to resolve the core legacy problems at the site and would only serve to delay any potential decision regarding closure."
The Broxburn plant was competing against much larger, modern units across Europe and bringing the facility up to date would cost in excess of £100m and take up to two years of mounting losses to complete, added the spokesman.
"Unfortunately the structural issues within the market and the problematic nature of the outdated facility, which we have been consistent about throughout this process, mean we have still not identified a viable solution for the Hall's site.
"We will continue to work through the remaining three weeks of the consultation process with our employees, their union representatives and the various stakeholders who have been involved in this process.
"Our focus now must be on how we can best support our people through the coming weeks."
Following the rejection of the proposals, Mr Swinney said the taskforce would now be concentrating its efforts on identifying profitability improvements, engaging with retailers to sustain contracts, providing advice to employees and working with two potential bidders to secure investment.
Quality Meat Scotland chairman Jim McLaren said it would be inappropriate to speculate about the outcome of the discussions while the 90-day consultation was still under way.
The levy body would be working closely with Vion, the Scottish government and the wider industry to ensure every opportunity was taken to secure the future of the industry in Scotland and allow it to move forward with confidence, he added.
The taskforce is set to meet again in early October - the 90-day consultation period ends on 3 October.
Hall's of Broxburn plant's future uncertain
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