The US and Europe have agreed to lift restrictions on flights across the Atlantic.
Airline mergers could be made easier by further liberalisation
The breakthrough "open skies" deal follows years of talks aimed at liberalising air services between the US and Europe.
The deal still requires the approval by the US and the 25 EU member states.
Currently, flights between the US and EU are restricted by a number of bilateral deals that have been negotiated by individual governments.
The deal was negotiated by the European Commission, forcing a wider opening of transatlantic air travel that goes beyond a string of bilateral treaties between the US government and individual EU member states.
Fundamental changes ahead
Under Friday's deal, US airlines will be free to fly both to airports in the European Union and from there to third destinations.
Similarly, European airlines will be able to fly to US airports and from there to other destinations.
An open skies agreement could see major changes to trans-Atlantic services from London's Heathrow airport, with the US keen to secure wider access for its carriers.
Experts say full liberalisation between the EU and US could transform the industry, leading to mergers between airlines.
However, Friday's deal falls short of opening up for total foreign ownership of US airlines.