The renminbi's fall to a five-year low against the US dollar has triggered a currency exchange boom on the Chinese mainland, forcing the regulator to strengthen intervention to ease capital outflow pressure.

An increasing number of people have been asking banks to change the Chinese currency into dollars, Guangzhou Daily reported on Monday.

Since last week, they have also been buying more foreign currency-denominated financial products, with most using up their annual currency exchange quota, the report said.