(January 11, 2010) — Abu Dhabi Investment Authority (ADIA), with estimates of its holdings ranging from less than $400 billion to $875 billion and up, revealed in a German business daily Handelsblatt interview that despite the global downturn, it sees “significant, long-term investment potential” in the U.S. and Europe.

These two areas house the bulk of ADIA’s holdings, with up to 50% and 35% of its assets respectively. Ten percent to 20% are in Asia.

Sheikh Ahmed bin Zayed al Nahayan, managing director of ADIA, the world’s biggest sovereign wealth fund, said that U.S. treasuries, still the most liquid benchmark, will continue to be an imperative diversification tool. Nevertheless, ADIA plans to tweak its investment approach to cope with the rough economic climate.

“You can be sure that, like everyone else, we are looking closely to identify areas where strategies perhaps did not work as well as they could have, and will refine our approach where needed,” said Sheikh Ahmed, according to Reuters.

ADIA officials rarely discuss the fund’s investments.