The Sunday Post is reporting that it has seen emails showing the loss-making airport is touting for business by offering to wave all landing and navigation fees for a commercial customer.
Transport Scotland, which owns the airport, says the move is fairly common practice in the industry.
They report an airport spokesman as saying:
"We’ve continually voiced our concerns from the outset over the Scottish Government’s business case for Prestwick Airport."
MSP Jackie Baillie also spoke out saying:
“There are clear anti-competitive and market distortion concerns if this sort of behaviour is going on."