The Gulf Arab emirate of Abu Dhabi announced it will invest 7.5 billion dollars for a stake in Citigroup Inc.

This way the largest US bank obtains much needed cash infusion after sustaining heavy losses in the subprime mortgage crisis.

Citigroup said that the "long-term" investor will receive no more than 4.9% of its capital and won't get a seat on the board. This holding would exceed the 3.6% controlled by Prince Alwaleed bin Talal bin Abdul Aziz al Saud of Saudi Arabia.

Citigroup earlier this month announced that it will see revenues decline 8 billion to 11 billion dollars on losses related to subprime mortgages - loans to people with poor credit. Its chief executive Charles Prince resigned as a result. The bank is still looking for a permanent replacement.

"This investment, from one of the world's leading and most sophisticated equity investors, provides further capital to allow Citi to pursue attractive opportunities to grow its business," acting chief executive Win Bischoff said in a statement.

The credit crisis has led to billions of dollars in writedowns at the top banks and lenders in the United States since an unprecedented number of defaults in home mortgages this summer.

"This investment reflects our confidence in Citi's potential to build shareholder value," ADIA Managing Director Sheikh Ahmed bin Zayed al-Nahyan said in the Citigroup-released statement.

The deal is the third big investment in a multinational made in recent weeks by the oil-rich sheikdoms of the United Arab Emirates. An investment vehicle of the ruler of Dubai announced earlier Monday that it was buying a stake in Sony that was also believed to be under 5%, and a state-run Abu Dhabi fund struck a deal November 16 to take an 8.1% stake in AMD.