The central banks of Australia and China signed a 200 billion yuan ($31 billion) currency swap to support trade and investment.

China has signed a slew of such agreements recently, trying to make its currency more internationally accepted.

The Reserve Bank of Australia says Thursday the agreement comes after China allowed the Australian dollar to be exchanged for yuan in China's bank-to-bank market.

It says the agreement reflects increasing opportunities for the yuan to be used to pay for exports and imports between the two countries.

Much of the world's trade is carried out in US dollars.

The agreement allows for the exchange of the currencies between the two central banks and is for an initial three year period.