Campaigners fear Levenmouth could lose out on plans for a freight terminal for the new railway line.
A new freight facility in the area could create jobs and help regenerate Methil Docks.
And siting it near Diageo’s vast Levenmouth operations would also remove tens of thousands of HGVs off local roads every year.
However, Network Rail confirmed it is still in talks over possible locations for a terminal for the line, which opens in 2024.
And as the biggest potential user, Diageo’s input is key.
The firm operates Europe’s largest grain distillery at Cameron Bridge, as well as a 150-acre bottling plant in Leven.
And it generates an estimated 20,000 lorry-loads each year.
But members of the Levenmouth Rail Campaign Group are concerned the drinks giant’s £150 million investment in warehousing at Cluny, near Thornton, could prove significant when it comes to locating a rail freight facility.
Would mean ‘no respite’ from HGVs
Chairman Allen Armstrong said: “It seems to be emerging that the preference for a freight location is away from Levenmouth itself.
“We understand the creosote works in Methil remains a possible alternative if a preferred option in central Fife cannot proceed.
“But if no freight terminal appears in Levenmouth then there are several negative consequences for this area.
“Firstly, there will be no respite from the thousands of yearly HGV movements on congested local roads.
“And there will certainly be no reduction in local carbon emissions or pollution.
“There was a clear Scottish Government commitment to a freight terminal for Levenmouth.
“And this is part of the Network Rail remit for the line.
“If this does not materialise, then the associated commitment to carbon reduction also starts to look questionable.”
Network Rail: ‘Constructive discussions ongoing’
Mr Armstrong added: “The campaign understands freight requires a working partnership between state and private sector.
“But if a commercial operation is able to dictate terms of what will be a major public investment, then the community in Levenmouth will be the loser.”
Network Rail confirmed talks were ongoing.
And a spokesman said: “Network Rail is working towards delivering on the scope of the project, which is to enable a rail connection to accommodate a future rail freight terminal.
“Constructive discussion are ongoing with Diageo, Fife Council and other industry partners to assess and define the optimal location for any freight facility.”
Diageo did not respond to requests for comment.