Some of the world's largest sovereign wealth funds are seeking to scale back their exposure to the US dollar in a sign of global concern about the currency.

One big sovereign fund in the Gulf has cut its dollardenominated holdings from more than 80 per cent a year ago to less than 60 per cent, while China's State Administration of Foreign Exchange (SAFE) has been looking to strike deals with private equity firms in Europe as part of a strategy to reduce its dollar holdings.