The running mate of one of Kenya's two frontrunners in the presidential election alleged Thursday that the ballot count has been rigged.

Kalonzo Musyoka, Kenyan Prime Minister Raila Odinga's running mate, told reporters in Nairobi that his campaign has evidence that the vote tallying have been "doctored,” and lacks integrity, news agencies reported.

Odinga, son of Kenya's first Vice-President Jaramogi Oginga Odinga, has been trailing behind his rival, Uhuru Kenyatta, son of first President, Jomo Kenyatta.

"We as a coalition take the position the national vote-tallying process lacks integrity and has to be stopped and re-started using primary documents from the polling stations," Musyoka was quoted as saying by the BBC.

"It is not a call to mass action. We are committed as a coalition to the principle of the rule of law," he said.

The allegation came a day after election officials said the new electronic voting system had broken down, severely delaying the counting of ballots cast in Monday’s election and forcing the tallying to be done manually.

Election officials said the final results could be released as early as Friday, but they are legally allowed to finish the count by Monday.

The winning candidate is required to secure more than 50 percent of all votes cast or face a second-round of vote in April.

As of Thursday, Kenyatta has been maintaining his lead over Odinga, with 2.5 million (53 percent) votes to 1.9 million (42 percent).

Earlier, Kenyatta’s Jubilee Coalition had accused Britain of interfering in the election, Kenyan media reported.

The accusations prompted the U.K. Foreign Office to release a statement Wednesday saying the “claims of British interference, including by the High Commission, in the electoral process are entirely false and misleading.”

Disputed presidential elections in December 2007, following Odinga’s claims of foul play, had lead to riots in which more than 1,000 people died, the worst bout of violence since the nation gained independence from Britain in 1963.

The government and opposition came to a power-sharing agreement in February 2008 and a cabinet was formed in April the same year.

Kenya, the largest economy in East Africa, is a major U.S. ally in the war against Islamist militants in the region. Odinga had said in January 2008 that he is a distant relative of then-U.S. presidential hopeful Barack Obama.