Ian Khama was sworn-in on Tuesday as Botswana's fourth democratically elected president, pledging to diversify the country's diamond-dependent economy.

"We have long recognised that the diversification of the economy, both within the minerals sector and beyond, is a key strategy for our future survival," said Khama.

The economy of Botswana, which is the world's top diamond producer has been hit by the global decline in commodity prices.

However Khama said "diversification of our economy and the combined effect of our investments in the various sectors will result in job creation as well as poverty alleviation."

The inauguration ceremony was held in the grounds of the parliament building in Gaborone.

Khama's Botswana Democratic Party (BDP) sailed to a landslide victory in polls last Friday, clinching 45 of the 57 parliamentary seats, while the main opposition lost nearly half its seats to a splinter party.

The vote was the first election test for Khama (56) son of Botswana's founding father and a former military commander, who took over when his predecessor retired in April 2008.