Zimbabwe's presidential election results are the culmination of a deeply flawed process and do not represent the will of the country's citizens, U.S. Secretary of State John Kerry said on Saturday.
"In light of substantial electoral irregularities reported by domestic and regional observers, the United States does not believe that the results announced today represent a credible expression of the will of the Zimbabwean people," Kerry said in a statement.
Zimbabwe's Movement for Democratic Change (MDC) plans a court challenge against the election victory by President Robert Mugabe's ZANU-PF party which the MDC rejects as a fraud, MDC leader Morgan Tsvangirai said on Saturday.
"We are going to go to court, we are going to go to the AU (African Union), we are going to go to the SADC (Southern African Development Community)," Tsvangirai angrily told a news conference in Harare.
The MDC leader, who has been serving as Prime Minister in a fractious unity government under Mugabe, said his party totally rejected official results from Wednesday's election showing ZANU-PF winning a massive landslide victory and gaining more than two thirds of seats in parliament.
"We did not lose this election. It is in the imagination of ZANU-PF that they won," Tsvangirai said, adding that his party would present evidence in court to back its allegations that the July 31 vote was a "monumental fraud" engineered by ZANU-PF.
"I thought this election was going to resolve this political crisis. It has not. It has plunged the country back to where it was," Tsvangirai said.
The result of the election looks certain to extend 89-year-old Mugabe's 33-year rule in the southern African nation.
Africa's oldest leader, Mugabe has governed the former British colony, previously known as Rhodesia, since independence in 1980. It has rich reserves of chrome, platinum, coal, gold and diamonds.
The Zimbabwe Electoral Commission has until Monday to release the official results of the presidential vote.
- Zimbabwe protests weighed after election
Voting on Wednesday passed off peacefully and received broad approval from African observers.
Tsvangirai has already called on the African Union and SADC to investigate the vote, calling it "null and void" and "not credible".
But he faces an uphill struggle to convince the regional bodies, as their observers have already publicly endorsed the election as free and peaceful, while acknowledging minor problems.
Western observers were kept out by Harare, and independent domestic monitors have described the vote as deeply flawed by registration problems that may have disenfranchised up to a million people. This includes the lack of availability of an updated voters' roll, as required by law.
Adding to the controversy surrounding the election, one member of Zimbabwe's nine-member Electoral Commission, Mkhululi Nyathi, has resigned since the vote, citing doubts about the integrity of the results.
Tsvangirai's MDC said on Friday it could take to the streets to challenge ZANU-PF's claim of a landslide victory, made less than 24 hours after the polls had closed on Wednesday.