A new political party was officially launched in Botswana after breaking away from the ruling Botswana Democratic Party (BDP), citing strong differences with President Ian Khama.

The launch of the breakaway Botswana Democratic Party (BMD), formed by four parliament members, marks a change in the political landscape in Botswana, the world's largest diamond producer, where the ruling party has been in power since 1966.

"We decided to part ways with the BDP because we cannot exist within an organisation where democratic principles are overstepped. Dialogue is non-existent," Botsalo Ntuane, vice chairperson of the new party, said at the launch on Saturday.

The new party recently told a local publication that it expects about 25 members of parliament to join the party, which would increase the number of opposition members in parliament to 37, and might lead to a snap election, analysts said.

The BDP won 45 of the 57 constituencies in last year's election.