At least 18 Northern Ireland farms are among the businesses affected by Ulster Bank's latest loan sale, the Belfast Telegraph can reveal.
The bank this week confirmed it had sold its £2bn Project Oyster loan portfolio to US vulture fund Cerberus.
The fund also bought the Northern Ireland property portfolio of Nama, the Republic's bad bank, in Project Eagle.
As part of the deal, Ulster Bank has sold €2.5bn (£2bn) in loans, including 900 mortgages, across Ireland. It is understood around 12% of the overall debt is based in Northern Ireland.
The bank would not confirm the number of farmers affected - but the Ulster Farmers' Union (UFU) claimed that at least 18 farmers' loans had been included in the deal.
It means farmers now have to deal with Cerberus as their lender instead of Ulster Bank, which could mean a change in their terms and conditions. Melissa Wylie, an officer at charity Rural Support, said her organisation had received several phone calls from worried farmers.
"It's the uncertainty which is the hardest thing for farmers to deal with," she added. "They're not sure exactly what the terms of the new arrangement will be, or how it will affect them yet.
"There's also the disappointment and the sense they haven't been able to manage the farm as well as other generations."
In addition, some farms were third or fourth-generation family businesses, with ownership of the family home tied in, she said.
UFU president Barclay Bell stressed that it was important for farmers to continue to engage with their banks, whether or not they were affected by the latest transaction.
"It is disappointing that agri-loans have been included in this debt package sale," he added. "We understand that only a small number of farmers are involved, but I can imagine the impact this will have on those businesses and families.
"If anyone affected is a UFU member, I would encourage them to contact the union for advice and support. The UFU is keen to see banks continue working with their farm customers in an open and supportive way.
"Communication is key. I would encourage farmers to keep the lines of communication open and for banks to do the same.
"In most cases, the banks are already using the close relationships they have with customers to explore options before adopting more hardline strategies, and I would like to see this continue."
An Ulster Bank spokesman said the bank would contact all affected customers.
"Ulster Bank has confirmed the completion of a sale of an impaired loan portfolio, predominantly in the Republic of Ireland, enabling the bank to strengthen its balance sheet for the benefit of its customers," he added.
"The loans involved are all in Ulster Bank's problem debt management unit and have been in arrears or under specialist management for a significant period of time."