Malawi has awarded oil exploration licences to UK-based firm Surestream Petroleum to search for oil in the country's main lake, the minister of energy said on Monday.

We engaged Surestream Petroleum to do some exploration on the lake and we expect them to do a thorough environmental impact assessment before they can go any further, Goodall Gondwe told Reuters.

Surestream Petroleum was awarded exploration licences for blocks 2 and 3 in Lake Malawi, with a combined area of 20,000 square kilometres.

The independent oil exploration company currently has presence in several countries including the Democratic Republic of Congo and Burundi.

Lake Malawi has more than 500 different fish species and oil exploration on the fresh water lake will likely rile environmentalists who have in the past feared that such a venture would disturb its ecosystem.

William Chadza, executive director for Centre for Environmental Policy and Advocacy, said that recent investment trends in Malawi showed environmental issues were being ignored.

New investment in the mining (sector) has ignored environmental issues like in the case of the uranium mine ... we fear that the same will be the case in this venture, Chadza said.

Lake Malawi, which occupies one fifth of the country, is the main tourist attraction for the southern African nation.