Kenya's opposition leader Raila Odinga has slammed the country's presidential election re-run as "a sham" and has called for another vote to be held within 90 days.

The country has been engulfed in bitter divisions and political uncertainty after the repeat election was boycotted by supporters of Mr Odinga and deadly clashes erupted in some parts of the country between police and opposition supporters.

At least eight people have been killed by police in the protests since the vote and several opposition strongholds had to postpone voting because of security problems.

Speaking to the Associated Press in his home in an affluent Nairobi suburb, Mr Odinga warned Kenya was in "grave danger" following the August election rerun and that low voter turnout meant the latest poll was not valid.

Dismissing the vote, Mr Odinga added: "It was basically Uhuru versus Uhuru."

The 72-year-old opposition leader said he is open to dialogue with the Kenyatta camp about holding what he called free and fair elections.

"We are not unwilling to talk but the agenda will still be the same agenda — how to create a level playing field so that an election can be held in 90 days," he said.

With more than 90 per cent of the votes counted, the electoral commission said Kenyatta had won 7.1 million votes.

But Mr Odinga doubted the results and accused the electoral commission of boosting the number of votes for Mr Kenyatta.

Now fears of violence and clashes between tribes are rife. Tensions rose in western Kenya as a Luo man was killed overnight in clashes between the Luo tribe which supports Mr Odinga and the Kalenjin group which backs Mr Kenyatta.

Challenging President Uhuru Kenyatta, Mr Odinga accused the government of trying to "destroy other institutions of governance in our country" including the Supreme Court and called for electoral reform.

Thursday's election was the second time Kenyan voters went to the polls in three months after Mr Odinga, a Luo, successfully challenged his defeat in the August election.

Mr Kenyatta, a Kikuyu and Kenya's current president, won 54 per cent of the vote in this year's first poll when voters queued during the night to cast their ballot.

Kenya elections rerun: in pictures Show all 20 1 /20 Kenya elections rerun: in pictures Kenya elections rerun: in pictures Kenya elections rerun A National Super Alliance protester yells as nearby police officers Getty Images Kenya elections rerun: in pictures Kenya elections rerun Residents some brandishing swords, throw stones towards Kenyan police officials AFP/Getty Images Kenya elections rerun: in pictures Kenya elections rerun Supporters of National Super Alliance (NASA) presidential candidate Raila Odinga burn tires AFP/Getty Images Kenya elections rerun: in pictures Kenya elections rerun A security officer checks a voter before letting him participate in a presidential election REUTERS Kenya elections rerun: in pictures Kenya elections rerun Smoke rises from tear gas fired by riot policemen to disperse supporters of Kenyan opposition leader Raila Odinga REUTERS Kenya elections rerun: in pictures Kenya elections rerun An opposition supporter gestures with a knife during clashes with police in Kibera slum REUTERS Kenya elections rerun: in pictures Kenya elections rerun Riot police fire tear gas to disperse supporters of Kenyan opposition leader Raila Odinga REUTERS Kenya elections rerun: in pictures Kenya elections rerun Residents throw stones towards Kenyan police officials AFP/Getty Images Kenya elections rerun: in pictures Kenya elections rerun A protester prepares to throw back a teargas canister AFP/Getty Images Kenya elections rerun: in pictures Kenya elections rerun A Kenyan woman prepares to cast her vote by gas lamp, just after dawn AP Kenya elections rerun: in pictures Kenya elections rerun Opposition supporters run away from police in Kibera slum during clashes in Nairobi REUTERS Kenya elections rerun: in pictures Kenya elections rerun Supporters of National Super Alliance presidential candidate Raila Odinga burn tires AFP/Getty Images Kenya elections rerun: in pictures Kenya elections rerun People queue to cast their vote at a polling station REUTERS Kenya elections rerun: in pictures Kenya elections rerun Kenyan police officials react as teargas fills a street in Kibera AFP/Getty Images Kenya elections rerun: in pictures Kenya elections rerun Members of the Kenyan Independent Electoral and Boundaries commission check ballot boxes AFP/Getty Images Kenya elections rerun: in pictures Kenya elections rerun Kenyan police officers chase National Super Alliance protesters Getty Images Kenya elections rerun: in pictures Kenya elections rerun People cast their votes at a polling station REUTERS Kenya elections rerun: in pictures Kenya elections rerun Residents look on as Kenyan police officials walk towards a group of demonstrators AFP/Getty Images Kenya elections rerun: in pictures Kenya elections rerun A protester throws stones as riot police REUTERS Kenya elections rerun: in pictures Kenya elections rerun People queuing outside a polling station REUTERS

But a decision from the Supreme Court annulled the election result citing procedural irregularities including the electoral commission's refusal to allow its computer servers to be checked after allegations by the Odinga camp the system had been hacked in favour of Mr Kenyatta.

The decision sparked sharp criticism from Mr Kenyatta, who called the judges "crooks" and promised to "fix" the judicial system. He also warned the chief justice not to interfere with the electoral commissions as the country prepared for a second vote.

But refusing to recognise the latest election result, Mr Odinga said his National Resistance Movement will take up unarmed peaceful resistance and follow the example of civil rights movements led by Martin Luther King in the US and Mahatma Ghandi in India.

He added that in order to achieve his goal of holding fresh elections within 90 days, his movement will call for strikes, peaceful demonstration and boycotts.

"Our constitution actually provides for this.... if a regime is undemocratic, if a regime does not enjoy legitimacy, the people are justified to resist that regime," he said.