Brookfield and QIA have acquired 100% of the share capital of Canary Wharf Group and its parent company Songbird Estates for £2.6bn.
Canadian firm Brookfield teamed up with the Qataris to launch a joint bid to take control of Canary Wharf Group in December 2014. Just over two months later, in early February 2015, it was announced that the joint venture partners' 350p per share offer for Songbird had become wholly unconditional.
Songbird's shares will cease to trade on London's AIM market this week.
Brookfield Property Group CEO Ric Clark said: "Canary Wharf remains one of the most treasured property estates in the world. With the transaction now concluded, we look forward to working with QIA and the Canary Wharf Group management team to advance the substantial development pipeline and to realize the full potential of the site for our tenants, stakeholders and the people of London."