Qatar Investment Authority (QIA) has agreed to purchase Singapore’s Asia Square Tower 1 from US investment firm BlackRock for $Sing3.4 ($2.5bn), in the largest-ever single-tower real estate deal in the Asia-Pacific region.

The office tower in the central business district has more than 1.25 million square feet of net lettable area, according to a joint statement from QIA and BlackRock.

BlackRock, the world’s largest asset management firm, had to accept a lower price than it had originally anticipated for the 43-story tower, which has tenants including the US’ Citigroup and KKR & Company, as rents in Singapore declined amid slowing economic growth. BlackRock, which also owns Asia Square Tower 2, had last year said it could get more than S$4bn for Asia Square Tower 1 and that it might also sell Asia Square Tower 2, according to media reports.

Sovereign wealth fund for the world’s top liquefied natural gas (LNG) exporting nation, QIA’s real estate portfolio includes Los Angeles office buildings acquired earlier this year from US real estate investment trust Douglas Emmett for $1.34bn and London’s Canary Wharf Group and parent Songbird Estates. In 2015, Qatar was the second-biggest foreign purchaser of US offices, following its investment in US firm Brookfield Property Partners’ $8.6bn Manhattan West scheme.

QIA has globally invested about $38bn in property, with $21.7bn in office transactions and $7.5bn for hotels, including the 2014 purchase of the St Regis Rome, according to the US’ Real Capital Analytics. The fund may buy the luxury St Regis hotels in New York and San Francisco from the US’ Starwood Hotels & Resorts Worldwide, people with knowledge of the matter told US news agency Bloomberg in May.