The Indonesian government said Thursday the country has 22 unexplored blocks with potential reserves of up to 8.5 billion barrels of oil and 175 trillion cubic feet of gas.

The 22 offshore blocks have not been explored as exploration would be very costly, according to Amir Hamzah, spokesman for the Oil and Gas Executive Body (BP Migas).

Exploration in off-shore blocks is three times as expensive as onshore blocks, he said.

"We invite domestic and foreign investors to explore and exploit oil and gas in Indonesia," he was quoted by Antara news agency as saying during a visit to Jambi province on Sumatra island.

Most of the blocks are located in eastern Indonesia, including Sulawesi, Maluku and Papua, he said.

Source: Xinhua