UPDATE 1-Qatar Airways to join oneworld alliance - sources

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LONDON, Oct 2 (Reuters) - Qatar Airways will become the first Gulf carrier to join the oneworld alliance of airlines with an agreement due to be announced early next week, according to sources close to the alliance.

The sources said Qatar Airways' membership of the alliance, which includes IAG's British Airways and American Airlines , will be announced at a press conference in New York on Monday.

The announcement will be made alongside IAG chief executive Willie Walsh, American boss Tom Horton and oneworld CEO Bruce Ashby, the sources said.

Oneworld said it would not comment on speculation about a forthcoming event. Qatar Airways declined to comment.

Alliances were set up in the 1990s to help airlines take advantage of each other's marketing and traffic in the face of tightly-controlled bilateral traffic rights, but so far the Gulf carriers have refrained from joining as they build big networks.

The other two alliances are Star, which includes Lufthansa , and SkyTeam, whose members include and Air France-KLM

and U.S. carrier Delta.

(Reporting by Rhys Jones; Editing by Mark Potter)

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