Sub-contracting firms may be under threat because of payments being "unreasonably withheld" by main contractors, Finance Minister Sammy Wilson has warned.
In one case payment was kept back from a firm for 17 months, and such poor cash flow could force small to medium size enterprises (SMEs) into insolvency, he told MLAs.
His comments came after a meeting with representatives of the construction industry at Stormont to discuss how the hard-hit sector can be reinvigorated.
"Small, medium and micro businesses are particularly vulnerable to cash flow difficulties, and their viability can be threatened by the unreasonable withholding of payments due to them," Mr Wilson said.
"Some 98% of firms here are SMEs, and they account for 67% of employment. Anything that threatens the viability of SMEs may, therefore, have a significant effect on our economy."