Ministers had made the offer following discussions with a task force aimed at saving the jobs of the 1,700 workers at the closure-threatened plant.
The task-force includes Usdaw, West Lothian Council, Scottish Enterprise, Scottish Development International, Skills Development Scotland, Job Centre Plus, Quality Meat Scotland and local representatives.
Finance Secretary John Swinney revealed yesterday that the Swiss company had turned down the proposal, which would would have seen the Scottish Government, working with West Lothian Council and Scottish Enterprise, purchasing and leasing back the Halls site on a commercial basis to enable significant capital investment to be made.
He said: "Vion - whilst welcoming the innovative nature of the proposals -has advised the task force that the proposal is not sufficient to be acceptable to the company."
Today, Ms Hyslop, SNP MSP for Linlithgow, said: “I am extremely disappointed that Vion have chosen to reject out of hand the substantial and innovative offer which the Scottish Government made to ensure that jobs are saved.
“If another company now comes forward and makes clear that it is prepared to accept the Scottish Government’s offer, I believe that Vion must be prepared to step aside and let that happen.
“There is too much at stake for the local economy and the workforce deserves every support offered. The priority for everyone involved in the task force is to ensure that jobs are saved so we will continue to work to find ways in which the affordability of the plant can be improved and jobs are protected.”
Speaking after the fourth meeting of the task force yesterday in Broxburn, Mr Swinney said: "The Scottish Government has been working closely with a range of agencies over the last few weeks to produce a range of measures that can be taken to deliver a sustainable future for the plant at Halls of Broxburn.
"The Scottish Manufacturing Advisory Service has worked closely with the company to identify improvements to the performance of the plant. Savings of about £4m have been identified, which, along with other energy efficiency and sales and marketing measures could significantly improve the financial performance of Halls.
"I have also formulated a substantial proposal that would see the Government, working with West Lothian Council and Scottish Enterprise, purchasing and leasing back the Halls site on a commercial basis to enable significant capital investment to be made.
"Along with the Leader of West Lothian Council, Cllr John McGinty, I put these proposals last week to Peter Bekkers the chief operating officer at Vion International. Vion - whilst welcoming the innovative nature of the proposals -has advised the task force today that the proposal is not sufficient to be acceptable to the company.
"The task force is now concentrating on identifying profitability improvements, engaging with retailers to sustain contracts at Halls, providing advice to employees and working with two potential bidders to secure investment and we would invite any other interested parties to come forward. The task force will meet again in early October."
Mr Swinney today suggested that two other un-named parties have expressed an interest in the business.
He said buying the food factory would have cost about £2m and the proposed rescue plan was "essentially a commercial transaction", adding: "What the public sector would have done would have been to partner the revival of the plant and to ensure that long-term investment could be delivered into the plant.
"That's the type of approach that I think is required when you're faced with such a significant economic impact as the potential of losing 1,700 jobs in a very small labour market in the West Lothian economy, centred around Broxburn."
The Finance Secretary went on: "What we were trying to do in this proposal was to recognise the fact that should Vion chose to close the plant, that's not a cost-free option for Vion. It will cost them in the order, I estimate, of between about £17 million and £25 million to close the plant.
"That's essentially a negative cost which I would rather see invested in the long-term future of the plant at Broxburn, creating a continuity of employment for members of staff."
Mr Swinney said Vion had been "very co-operative" with the task force since it was established.
"These proposals have been fully considered by Vion and the company have made their own decision, and they're perfectly entitled to do that," he said.
"What's important is the Government, our agencies and our local authority partners continue to work together to support the workforce at what's clearly a very difficult time, and to take forward any other possibilities for other interested parties to become involved in looking for some creative solutions at the plant."
With less than three weeks to go until the 90-day consultation closes on October 3, Mr Swinney said other parties have expressed an interest in the plant. He said: "I saw a potential bidder yesterday and Vion have another registered note of interest from another party.
"Obviously we're in a situation where I think any interested party who wishes to take forward the possible leadership of the Halls of Broxburn plant must do so, and must do so very urgently."
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