ALGIERS, Algeria -- Algeria's energy minister says a new oil field containing an estimated 1.3 billion barrels has been discovered. The energy minister, Youcef Yousfi, told the state news agency Saturday that the discovery near the large oil fields in the southern region of Hassi Messaoud is one of the most important in the last 20 years. He added that the state oil company, Sonatrach, will rely on unconventional techniques to extract 50% of the reserves, including hydraulic fracturing, also known as fracking. The field will be exploited in the next three to four years following the necessary studies, the report added. Algeria, an energy giant in Africa that already is one of the largest natural gas suppliers to Europe, had been concerned about declining oil reserves.