The Fine Gael leader, Enda Kenny is demanding an explanation from Deputy Beverly Cooper Flynn, over reports that she received a €74,000 cheque from property developer Tom Gilmartin.
Ms Cooper Flynn is denying the allegations.
Enda Kenny says Deputy Cooper-Flynn needs to make a personal statement on the issue.
He said his party would make its Dáil time available for her to do so.
FG's Bernard Durkan said the issue must be fully debated.