Kuwait's Oil Minister Sheikh Ali al-Jarrah al-Sabah confirmed on Saturday that Kuwait's proven oil reserves are 48 billion barrels -- a figure conflicting with the previous official estimates of nearly 100 billion barrels.

In an interview with a Kuwaiti newspaper, Sheikh Ali Al-Jarrah said unproved oil reserves in the country may reach 150 billion barrels.

The government had put its proven oil reserves at nearly 100 billion barrels, or 10 percent of the world's total oil reserves. But some media have raised doubts about the figure.

Sheikh Ali Al-Jarrah explained that there were often newly discovered oil and gas fields whose details were not published out of energy security concerns.

Different statistical methods may have also contributed to the discrepancy in figures, he added.

The Kuwaiti government announced recently the discovery of a rich oil field in northern Kuwait, but it did not disclose the size of the field.