Mugabe, 89, who has run the country since he helped end white rule in 1980, trounced his long-standing political rival, Morgan Tsvangirai, in Wednesday’s election, Zimbabwean election officials said.
By the time he completes his new tenure, he will have ruled the former British colony in southern Africa for 38 years.
Official results showed Mugabe won 61 percent of the presidential vote and his party got a super majority in parliament that will allow it to change the constitution. He routed Tsvangirai who trailed heavily with 34 percent.
But 61-year-old Tsvangirai, who has unsuccessfully tried to unseat Mugabe three times, condemned the vote as “fraudulent and stolen”.
The reaction in the Sunday press was divisive with state-controlled newspaper The Herald proclaiming “President Mugabe romps to victory”, while the independent Daily News said “It’s a crisis”.
US Secretary of State John Kerry meanwhile described the election as “deeply flawed” and said the US “does not believe that the results …today represent a credible expression of the will of the Zimbabwean people.”
British Foreign Secretary William Hague added his own “grave concerns” over the conduct of the vote in the former colony.
On Sunday, Australia called for Zimbabwe to go to the polls again.
“Given our doubts about the results, Australia calls for a re-run of the elections based on a verified and agreed voters roll,” Foreign Minister Bob Carr said in a statement.
Tsvangirai vowed to challenge the result in court and said his Movement for Democratic Change (MDC) would boycott government institutions.
“We will not join government,” he said. “We will go to court.”
“The fraudulent and stolen election has plunged Zimbabwe into a constitutional, political and economic crisis.”
With gentler assessments from African observers who nonetheless noted flaws, President Jacob Zuma of powerful neighbour South Africa offered his “profound congratulations” to Mugabe on Sunday.
“President Zuma urges all political parties in Zimbabwe to accept the outcome of the elections as election observers reported it to be an expression of the will of the people,” a foreign ministry statement said.
Tsvangirai has been in a coalition with Mugabe since 2009. He defended the decision then to enter into an uneasy power-sharing government with Mugabe, who has had him arrested, beaten and charged with treason.
“Our participation rescued this country. Schools had closed, hospitals had closed. We were using the Zimbabwe dollar which was worthless, there were no goods in the shops, everyone was desperate,” he said.
But Mugabe’s ZANU-PF party says there is no more need for the MDC in the new government.
“We have received over 60 percent of the vote, we have two thirds majority, why would we want to bring someone else on board,” State Security Minister Sydney Sekeramayi said to AFP.
The MDC now has until Wednesday to present evidence of fraud to the high court, but finding a smoking gun may prove difficult. Inauguration is expected within 48 hours of the court’s decision.
Tsvangirai said he would submit a dossier of “all irregularities and all the illegalities” to the influential 15-member Southern African Development Community (SADC) and called for an urgent summit.
The European Union, which had been moving toward easing long-standing sanctions, expressed concern about “incomplete participation, as well as the identified weaknesses in the electoral process and a lack of transparency”.
But Emmerson Mnangagwa, defence minister and a key Mugabe lieutenant, hit back at these accusations and argued the result was a game-changer.
“The West will now have to climb down, they must find a ladder and climb down… A democratic election has taken place in Zimbabwe,” he told AFP.
The SADC, which engineered the power-sharing government, said it was “free and peaceful”.
“We did not say it was fair … we didn’t want to jump to a conclusion,” said top SADC election observer Bernard Membe.
However, the poll’s credibility was further called into question by the resignation of one of the nine official electoral commissioners.
In a letter seen by AFP, Mkhululi Nyathi quit over “the manner” in which the polls “were proclaimed and conducted”.
Tsvangirai stopped short of calling his supporters onto the streets, fearing a repeat of the bloody crackdown that followed his win in the first round of 2008 polls.
There was calm in the capital late Saturday, with little sign of protests or pro-Mugabe victory rallies. Streets remained quiet on Sunday.
Even before the official election results, Mugabe followers were planning how to use a parliamentary majority.
“The new constitution will need cleaning up,” said Justice Minister Patrick Chinamasa, referring to a text approved in March that introduced term limits and curbed presidential powers.
Chinamasa said Mugabe’s government would also press on with controversial efforts to bring firms under black ownership.
Investors have expressed fears that may mean rolling back the power-sharing government’s efforts to stabilise the economy after crippling hyperinflation and joblessness.