Under the new plans, governments would be able to grant state aid to cover 30-50 pct of the start-up costs accrued by airlines at regional airports over a maximum of five years.
The guidelines are for airports with fewer than 5 mln passengers a year. A commission spokesman said that in "exceptional cases" airports with 5-10 mln passengers would be looked at on a "case-by-case basis".
The public funding of airport infrastructure is also covered by the rules. National governments are free to finance new air transport infrastructure, but the commission will monitor the situation to ensure competition is effective.
"The new guidelines will increase transparency and prevent any discrimination in the agreements concluded by regional airports and airlines on start-up aid," the EU executive said.
The commission added that the rules will "guarantee" equal treatment for public and private airports and ensure that airlines receiving aid are not unduly favoured.
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