Foreign exchange reserve of the Indonesian central bank increased in July as the prospect of investment strengthens following credit rating upgrade by the top global rating agency.

The forex reserve of the lender was up to 127.759 billion U.S. dollars at the end of July from 123.094 billion dollars at the end of June, the bank said in a statement on Monday.

The hike was contributed by increases in foreign exchange revenues, including sales of the government's global bonds, revenue from oil and gas exports and sales of the central bank's debt papers in foreign currency, spokesman of the central bank Agusman said in the statement obtained by Xinhua.

The amount of the forex reserve is sufficient to finance nine months of importation or 8.7 months of importation and payment of government foreign debts, exceeding the international threshold of three months, he said.

S&P Global rating agency upgraded Indonesia credit rating to investment grade with positive outlook in May.

That was years after Indonesia got such level of upgrade from Fitch and Moody's credit rating agencies.

Indonesia has enjoyed a rapid inflow of capital in recent years amid a reform in investment sector and sound macroeconomic fundamentals.