The deal will be the first completed under a framework created by the Group of 20 major economies and the Paris Club in late 2020 to help poor countries weather the covid pandemic.
Chinese firms have been involved in 89 announced acquisitions and investments in Canadian metals and mining companies in the past decade, according to Bloomberg data.
Rio has struggled to win investor support for the Turquoise Hill deal, forcing it to offer unusual terms to the most stubborn holdouts which appeared to be enough to close the deal.