Oneworld carriers British Airways, American Airlines and Iberia have received clearance from the European Commission for their proposed transatlantic tie-up.
The decision follows commitments from the airlines offered in order to allay competition concerns over their planned joint venture.
In a statement the Commission says it has "made legally binding" the commitments from the carriers.
Among the concessions offered by the carriers were slots at London Heathrow to allow the entry or expansion of competitors on routes to the US cities of New York, Boston, Dallas and Miami.
"After a market test, the Commission concluded that the commitments offered were suitable to remedy the competition concerns and has closed its investigation," the Commission says.