Robert Mugabe has been sworn in for a new five-year term as Zimbabwe's president after election officials declared a landslide victory for him.
A 21-gun salute and military jet fly-by greeted Mr Mugabe at the ceremony at his State House residence in Harare.
Official results said Mr Mugabe won all 10 provinces with 85.5% of the vote - but there were many spoiled ballots.
He was the only candidate to run after the opposition boycotted the vote amid claims of state-sponsored violence.
Electoral commission officials said voter turnout had been about 42%, similar to that of the disputed first-round vote in March.
Independent observers said many of those who did go to the polls voted out of fear, and that thousands of people had spoiled their ballots by defacing them or marking them inaccurately.
The hastily organised ceremony confirmed Mr Mugabe's sixth term as president - extending his 28 years in power.
"I, Robert Gabriel Mugabe do swear that I will truly serve in the office of president, so help me God," the 84-year-old said, to applause from the gathered dignitaries.
Opposition leader Morgan Tsvangirai was invited to the ceremony as a "gesture of engagement", but he rejected it as "meaningless".
An opposition spokesman said Mr Mugabe's appointment was "an absolute joke" as he did not have the mandate of the people.
Mr Tsvangirai, leader of the Movement for Democratic Change (MDC), announced he was pulling out of the election last Sunday citing violence and intimidation against his supporters.
But his name remained on ballot papers after Zimbabwe's electoral authorities refused to accept his decision.
Mr Mugabe is now expected to fly to Egypt to attend an African Union summit which opens on Monday.
The BBC's Peter Biles, in Johannesburg, the question now is whether Zimbabwe's neighbours will recognise this election result.
An observer team from the Pan-African Parliament has called for fresh elections to be held, saying the vote was not free or fair.
It has called on regional grouping Sadc and the African Union (AU) to facilitate talks between the government and opposition.
Earlier, the former Archbishop of Cape Town, Desmond Tutu, urged the international community to intervene in Zimbabwe - by force if necessary.
He said he would support the deployment of a UN force to restore peace in the country.
Speaking on the BBC's Andrew Marr programme, Archbishop Tutu also said that AU leaders should refuse to recognise Robert Mugabe as the legitimate president of Zimbabwe.
"If you were to have a unanimous voice, saying quite clearly to Mr Mugabe... you are illegitimate and we will not recognise your administration in any shape or form - I think that would be a very, very powerful signal and would really strengthen the hand of the international community."
There has also been international outrage at events in Zimbabwe.
US President George W Bush on Saturday instructed US officials to come up with new sanctions against Zimbabwe, and said the US would press for strong action by the UN.
In interviews published in British newspapers on Sunday, Mr Tsvangirai said he would push for negotiations with Mr Mugabe on a new constitution and fresh elections.
"We have the power to control parliament, and that is recognised even by Mugabe's Zanu-PF... We must force a transitional agreement for a set time-frame and work towards a new constitution for Zimbabwe," he told the Mail on Sunday.
"I am confident we can achieve that if international pressure keeps up," he added.
Mr Mugabe came second to Mr Tsvangirai in the first round of the presidential vote in March.
Since then, the MDC says some 86 of its supporters have been killed and 200,000 forced from their homes by militias loyal to the Zanu-PF.
The government blames the MDC for the violence.
BBC NEWS | Africa | Defiant Mugabe seals sixth term