Qatar says it has discovered as much as 2.8 trillion cubic feet of natural gas in an offshore field.
Energy Minister Mohammed bin Saleh al-Sadah told reporters on Sunday the discovery was made at the field known as Block 4 North, off the shore of the Gulf state.
The field is operated by Qatar Petroleum along with its partners Mitsui Gas Development Qatar and Germany's Wintershall.
Al-Sadah, who is also managing director of Qatar Petroleum, said "we are very pleased" with the discovery.
He said it was part of an effort by the country to "prudently explore for and develop our natural resources" as part of the contribution to the country's economic prosperity.
OPEC member Qatar is a major exporter of oil and natural gas.