Botswana's President Ian Khama is to be sworn in for another term on Tuesday after winning the country's election, Botswana media report.

The  government-owned Daily News and the independent Mmegi newspaper said Chief Justice Maruping Dibotelo had declared Khama elected president on Sunday.

This came after his Botswana Democratic Party (BDP) had won a majority of the 57 seats in Parliament.

The BDP won 37 seats, the Umbrella for Democratic Change - contesting an election for the first time - 17 seats, and the Botswana Congress Party (BCP) three seats.

Mmegi said Khama has lost six former cabinet members in the election and that the BCP had lost key constituencies it had held in the past.

News agencies suggest that the BDP is losing support in urban areas.

In Gaborone, observers from the Southern African Development Community, declared that the election on Friday had been "peaceful, free and fair, transparent, and credible, thus reflecting the will of the people of Botswana..."

South African foreign minister Maite Nkoana-Mashabane said the election "marks yet another milestone in the long standing democracy" of Botswana.

"Botswana remains unique in Africa in that it has enjoyed 48 years of sustained and uninterrupted democracy," she added. "This achievement should be emulated by other SADC Member States in their efforts to consolidate and enhance democracy in the region."