The Minister for Transport, Mr Brennan, told the European Commission yesterday that its draft ruling that Ryanair had received illegal subsidies threatened to damage regional airports and the whole low-cost airline industry.

Mr Brennan said he was concerned by reports that the commission would demand Ryanair pay back millions of euros of state aid given by the Walloon regional government at Charleroi Airport, the airline's Belgian hub. The college of commissioners is to consider the ruling next Tuesday.

Ryanair's deputy chief executive, Mr Cawley, said yesterday that the airline would appeal against an adverse ruling.

Mr Brennan was in Brussels to chair negotiations on aircraft safety. Asked if he had raised Ryanair with the transport commissioner, Ms Loyola de Palacio, he answered: "I said that if reports I am hearing are true, there is potential for it to be detrimental to airports and airlines across the board."

Mr Brennan said he was concerned about the effect on Aer Lingus, not just on Ryanair. He said he might put the issue on the agenda of a meeting of EU transport ministers in March and it may be considered by the March European summit of EU leaders.

A spokesman for Ms de Palacio, Mr Gantelet, said yesterday that the commissioner agreed with Mr Brennan that the ruling had implications for the whole aviation sector. "In this concrete case, we have to ensure that there is nothing illegal and that the laws are not violated. That is what we are going to do," he said. "We want to ensure that they can have real development but it must be based on fair, non-discriminatory markets."