US Republican congressman Chris Collins, has resigned ahead of his expected guilty plea in a criminal insider trading case on Monday.

The criminal case is related to Australian biotechnology company Innate Immunotherapeutics Ltd, a company for which Chris Collins sat on the board and held a 16.8% stake.

Mr Collins is scheduled to appear in the Manhattan Federal Court to enter his guilty plea, along with his son Cameron Collins, and another man Stephen Zarsky who will also plead guilty, court records show.