Workers at a government-owned helicopter maintenance plant near Perth have been told a decision on its future will be made within a month.
Unions believe the plant should not be privatised
UK minister Baroness Taylor, who will decide the fate of the Defence Aviation Repair Agency (Dara) plant at Almondbank, was on a visit to the site.
The defence equipment minister told workers they would have nothing to fear from privatisation of the business.
About 350 staff at Almondbank carry out repairs for the Ministry of Defence.
However there are plans to sell the company to Canadian firm Vector Aerospace.
Lynx, Sea King and Chinook helicopters are repaired at Dara, but the first two are being phased out.
It is feared that could lead to job losses, and even the eventual closure of the plant.
Ministers have claimed that privatising the business would allow staff to work on commercial projects and retain their skills.
Baroness Taylor said: "Whilst people are apprehensive about change, I think Almondbank has proved that it can change and that it has potential to change even further.
"I don't think there's anything to fear from privatisation.
"But I do understand why people are apprehensive and want all their concerns to be properly taken into account."
About 350 people work at the site in Perthshire
However the Unite union is opposed to any sell-off, fearing it would not be in the best interests of the armed forces or staff at Dara.
Ian Waddell from the union said: "We believe, not only in terms of jobs, pay, terms and conditions, but in terms of helicopter support and the capability of supporting the frontline services, we believe that retaining this work in house, under MoD control, is absolutely the right way forward.
'We'll keep fighting to put that point across, even if that means delays in the decision."
Commenting on when a decision on Dara's future would be made, Baroness Taylor said she would be surprised if it took longer than a month.
"We're not talking a long time, because this decision has been hanging around for quite a while.
"We could have made it back in November but I agreed to take on board all the comments that were being made, both from Gordon Banks, the local MP, and from the trade unions and following my meeting today.
"We've got most of the information we want but I don't want any loose ends, I don't want not to take into account something that's been raised we with me."