Nigerian shipowners are demanding answers over $300m said to be missing from the national Cabotage Vessels Financing Fund (CVFF).
The cash was paid in between 2008 and 2015.
This Day reported that the National Ship Owners Association (NISA) have voted to press the minister of transport, Rotimi Amaechi, and potentially take legal action.
They are also asking for $124m contributed by owners since 2015 to be paid out.
The CVFF is managed by maritime authority NIMASA.
NISA president Aminu Umar told the newspaper: “We have deliberated on the matter and we have set up a committee to find out how the money was spent, what it was spent on.
"Yes we know there is another $124m or $150m that was contributed between 2015 and now. But we have to first find out what happened to the last one that we contributed."
Director general of NIMASA, Dakuku Peterside, has recently said the agency would start paying the money out next year.