Kenyan opposition leader Raila Odinga urged supporters to stay away from work on Monday and accused the government of having planned to rig elections and murder his supporters.

"(The) Jubilee (party) have spilt the blood of innocent people. Tomorrow there is no work," Odinga told a crowd of around 4,000 cheering supporters in Kibera, Nairobi's biggest slum.

He was speaking after anger erupted in Kenya following President Uhuru Kenyatta's re-election last week.