Air Berlin - Europe's fifth largest airline - is to join the Oneworld group.

And Air Berlin group member Austria's Niki will become an affiliate member of the alliance.

A memorandum of understanding between Air Berlin and Oneworld was completed in Berlin Tuesday night, with a formal alliance membership agreement to be signed soon.

Air Berlin is expected to start flying as part of Oneworld in early 2012 - just weeks before the opening of the new Berlin Brandenburg International Airport, which is being built as a major new hub for Europe.

The carrier in 2009 served 160 destinations in 40 countries, operating almost 600 daily departures. It carried 28 million passengers, generating revenues of US$4.5 billion. As of July 2010, Air Berlin operates a fleet of 165 aircraft, including Austria's Niki, serving 168 destinations.

When it becomes part of Oneworld, it will add almost 75 gateway airports to the Oneworld map, expand the alliance's coverage to almost 900 destinations in nearly 150 countries, served by a combined fleet of 2500 aircraft operating some 9500 flights a day and carrying 340 million passengers a year.

Members of Air Berlin's topbonus frequent flyer programme will be able to earn and redeem rewards on any of Oneworld's 13 other top-class carriers, with top tier members able to use any of the group's 550 plus airport lounges, and its network will be covered by Oneworld's full range of alliance fares. Frequent flyer cardholders of Oneworld's established airlines will be able to earn and redeem rewards when flying Air Berlin.

As a starting point in its Oneworld implementation, Air Berlin will develop one-on-one co-operative agreements with key established members of the alliance American Airlines and Finnair, to take effect this coming winter season. Bilateral agreements with British Airways and Iberia are planned to follow.

British Airways will support Air Berlin through its Oneworld implementation programme as its alliance sponsor.

Air Berlin Chief Executive Joachim Hunold said joining a global alliance is the logical next step in Air Berlin's development.

"We are very pleased and proud to be lining up to join what is clearly the world's top quality airline grouping. Becoming part of Oneworld would be one of the most significant departures so far for our airline, enabling us to offer our customers a truly global network served by partners who include some of the best and biggest airlines in the world. We look forward to completing all joining requirements as soon as possible."

Already in Oneworld's "breakthrough year":

* Russia's leading domestic carrier S7 Airlines is on track to join in the coming months.
* India's leading carrier Kingfisher Airlines became a Oneworld member elect in June.
* Japan Airlines has been expanding its co-operation with its Oneworld partners since reaffirming its membership of the alliance in February, filing days later with American Airlines for anti-trust immunity for a joint business across the Pacific and more than doubling its code-sharing with British Airways.
* American Airlines, British Airways, Iberia, Finnair and Royal Jordanian this month received long-awaited final approval for their application for anti-trust immunity across the Atlantic and the proposed transatlantic joint business between American, BA and Iberia.
* British Airways and Iberia are on track to complete their merger by the end of the year.
* LAN Airlines celebrated its 10th anniversary as a Oneworld member on 1 June. Since joining, it has added to the grouping its affiliates in Argentina, Ecuador and Peru.
* Oneworld added the World Airline Awards' World's Best Alliance title to the World Travel Awards' World's Leading Airline Alliance trophies it has won for the past seven years, as the only winner of that award since it was introduced in 2003.