The cost of making long-awaited upgrades to the Avon Gorge has now reached £70 million - making the project "unaffordable" without significant government help.
Members of Falkirk Council hope to reach an agreement with West Lothian Council and Transport Scotland that will put them in a position to apply for any more UK Government Levelling Up funding that might be released.
The most recent review of costs, in 2020, had suggested that improvements to the steep, narrow road through the gorge would cost around £50 million. Since then, however, changes to technical standards have made the plans out of date.
Bridging the gorge and improving the A801 has been talked about for decades, and planning approval for the current scheme was obtained in 2009.
The route is regarded as vital, not just to West Lothian and Falkirk, but to the Scottish economy as a key link between the M8 and M9 and it is well used by haulage and distribution firms despite its reputation as an accident blackspot.
But with three partners involved, getting agreement and funding has so far proved impossible - and the current economic situation which has seen costs soar has put it further out of reach than ever.
Falkirk Council had previously agreed to use £12 million of Tax Incremental Finance (TIF) funding, which means borrowing money for infrastructure projects against future rates that are expected to be generated by the investment.
But the spiralling prices mean that even with maximum TIF funding, Falkirk Council would find itself £5.5 million short.
West Lothian has no cash allocated to the project at all, and would need to find the full £17.5 million, although it is currently applying for different funding to put traffic signals on the junction between the A801 and the A706 in a bid to cut the number of accidents.
Even Transport Scotland, having been allocated £22 million for the project by the Scottish Government in 2020, now finds itself £13 million short.
Officers are now pinning all their hopes on a joint bid to the UK Government's Levelling Up Fund, even though the third round of funding has not yet been announced.
The hope now is that the two councils and Transport Scotland can work together and will soon sign a 'memorandum of understanding' that will outline the responsibility of each of the parties.
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