The European Union (EU) and the United States are at row on the so-called "Open Skies" aviation deal between them, Brussels-based news website EUpolitix reported on Wednesday.
Washington said Tuesday it would delay relaxing restrictions on foreign ownership of its airlines because US Congress needs more time to discuss security issues.
"We're not going to make the timetable we initially contemplated by the end of this month or early September. We can't do it," US transportation under secretary Jeffrey Shane said on Tuesday.
However, the EU wants to see the rules relaxed before signing any "open skies" agreement.
A senior EU transport official said the deal can be salvaged and signed by the end of this year.
"We regret the delay," said Stefaan De Rynck, spokesman for EU Transport Commissioner Jacques Barrot.
De Rynck added that acting US Secretary of Transportation Maria Cino has promised that the United States was still committed to reaching a deal with the EU by the end of this year.
The EU and the US have said they hope the pact could enter into force on March 25, 2007, before the summer traffic starts, a date experts say would be hard, but not impossible, to make.
The US had initially planned to have relaxed rules in place by early autumn, in time for an October open skies deal, after the two sides already missed an earlier deadline to sign the agreement.
An open skies agreement would bring together the world's two largest aviation markets and 60 percent of global traffic, allowing EU and US airlines to fly to wherever they want and charge whatever they want on trans-Atlantic flights.
However, under the present bilateral pacts, European airlines can fly to any US airport only from airports located in their home country.
That's to say, Air France can only fly to the US from airports based in France.
(Xinhua News Agency August 17, 2006)