Delta Air Lines is buying rights to fly between New York and London from rival United Airlines for up to USD$21 million, a Delta spokeswoman said on Monday.

Delta plans up to three flights a day between New York's John F. Kennedy Airport and London's Gatwick Airport, with the first expected to start in the autumn, spokeswoman Betsy Talton said.

It plans to add up to two more flights a day next year, Talton said.

Atlanta-based Delta, which is operating under bankruptcy protection, would pay USD$13 million to United Airlines once the deal closed, with additional payments of USD$2 million per year, unless an "Open Skies" agreement were reached.

The United States and Europe have been in talks aimed at eliminating restrictions on service and routes between them under a so-called open skies agreement.

The Delta deal is subject to US Department of Transportation approval and other conditions. United will discontinue its service between New York and London's Heathrow Airport at the end of October.