Qatar Airways has finalised its agreement to acquire 35% of Cargolux, ending the Luxembourg State's temporary participation in the freight carrier.
The two companies have also signed a draft commercial co-operation plan, details of which will be disclosed when the transaction closes "in the coming weeks".
SAirLines (part of the defunct Swissair Group) sold its 33.7% stake in 2009 to three existing shareholders (including Luxair, which holds a 52.1% stake) and the Luxembourg State.
The acquisition by Qatar Airways of 35% of Cargolux "marks the termination of the temporary role of the Luxembourg State as a shareholder in the company and enables other state-controlled shareholders who participated in the 2009 restructuring planto sell or reduce their ownership in Cargolux", said Qatar Airways and Cargolux in a statement.
Qatar Airways chief executive Akbar Al Baker said the Doha-based carrier plans to "fuel our growth plans by including air freight as a major part of our product offering".
"Our investment in Europe's leading cargo carrier Cargolux boosts our ambition to become one of the major players in air freight by 2015," added Qatar Airways chairman Sheikh Hamad Bin Jassim Bin Jabr Al Thani.
"We have identified numerous synergies owing to the complementary nature of our businesses that will enable us to develop scale and reach and strengthen our respective hubs in Luxembourg and Doha," said Cargolux chief executive Frank Reimen.
Cargolux operates a fleet of 16 Boeing 747-400 freighters and employs more than 1,400 staff worldwide.
Financial terms of the deal have not been disclosed.