Kenya's parliament has rejected a bill to create 50 extra seats for women in a legislature with one of the lowest female representation in Africa.

The move was quashed when members of parliament (MPs) failed to back a constitutional amendment bill that would also, controversially, have created 40 new constituencies ahead of Kenya's December election, legislators said on Thursday.

The government-sponsored bill was rejected late on Wednesday after ministers were unable to raise the two-thirds of legislators required to pass it, they said.

Kenya has only 18 women members of parliament out of 222 -- a source of chagrin to the nation's highly active grassroots civil society groups.

While the move to increase female representation was widely supported, there was strong suspicion that the creation of new constituencies was a government trick ahead of the election.

During Wednesday's heated debate, speaker Francis Ole Kaparo ordered two women MPs -- on the verge of fighting -- to sit far apart and not speak to each other, local media said.

Outside parliament, dozens of women sang songs encouraging the lawmakers to pass the legislation.