Hong Kong's total assets of the exchange fund amounted to 2.49 trillion HK dollars (320.1 billion U.S. dollars) in May, up 43.4 billion HK dollars from the previous month, the Hong Kong Monetary Authority (HKMA) said Thursday.

In May, Hong Kong's foreign currency assets increased by 11.1 billion HK dollars and Hong Kong dollar assets rose by 32.3 billion HK dollars.

The rise in foreign currency assets was mainly due to an increase in unsettled purchases of securities, which was partly offset by a decrease in certificates of indebtedness, said the HKMA.

Meanwhile, the increase in Hong Kong dollar assets was mainly due to a rise in exchange fund bills and notes issued but not yet settled, which was partly offset by fiscal drawdowns.

Besides, the currency board account showed the monetary base at the end of May was 1.0499 trillion HK dollars, down 5.3 billion HK dollars from April. (1 U.S. dollar is equivalent to 7.78 HK dollars)