The European Commission has approved fresh funding of €65.5 million for the Republic's six regional airports. The money, which must be used to finance infrastructural developments at the airports, will be made available between now and 2010 by the Department of Transport.

The EU Commission said investments to improve safety and security could be granted aid of up to 90 per cent of eligible costs. Public funding for the expansion or improvement of facilities at the airport is allowed for up to 75 per cent of total costs.

The commission found that the proposed scheme of investment was in line with EU rules because the financing would not lead to "undue distortion" of the market.

The airports benefiting from the funding are: Donegal, Sligo, Knock, Galway, Kerry and Waterford.

All six airports are officially categorised by the EU as "small regional airports" and in 2005 they catered for 1.3 million passengers. It is understood there are 20 individual projects awaiting the funds.

Regional airports have been expanding their operations over recent years with increasing links to Britain and Europe. Some, like Cork, have even floated the idea of offering transatlantic services.

Growth in capacity by Aer Arann has played a central part in the growth of airports like Knock.

The original mission of the regional airports was to connect Dublin with outlying cities and towns, but this has radically changed over recent years. For example, services in Knock now stretch as far as Crete, Faro and Salzburg.

They are financed through a combination of Government funds and passenger charges. Some also charge a development fee that is used to fund runways and car parking facilities.