Bolsonaro set to speak after election loss

President Jair Bolsonaro is set to break his silence following his defeat in Brazil's presidential election, amid doubts over whether the far-right nationalist will accept the victory of his leftist rival, former president Luiz Inacio Lula da Silva.

Bolsonaro will speak to the nation later on Monday and his aides were suggesting he read a prepared statement, said Claudio Cajado, the head of a party allied to Bolsonaro.

It was not clear if Bolsonaro would concede defeat, as Cajado said some advisers were encouraging him to do.

Lula's win represents a stunning comeback for the 77-year-old former metalworker, who governed Brazil from 2003 to 2010 but then spent time in prison for corruption convictions that were later annulled.

Bolsonaro, who left his residence on Monday morning and headed to the presidential palace, has still not made any public comments. But prior to the vote he repeatedly made baseless claims the electoral system was open to fraud.

Lula has vowed to overturn many of Bolsonaro's policies, including pro-gun measures and weak protection of the Amazon rainforest.

The Supreme Electoral Court (TSE) declared Lula won 50.9 per cent of votes, against 49.1 per cent for Bolsonaro, who becomes the first Brazilian incumbent to lose a presidential election.

Lula's win consolidates a new "pink tide" in Latin America, and means the left will govern all the region's major economies after a string of electoral successes from Mexico to Argentina in recent years.

Bolsonaro's continued silence sparked fears over the handover of power.

His campaign did not respond to a request for comment.

International election observers said Sunday's election was conducted efficiently. One observer told Reuters that military auditors did not find any flaws in integrity tests they did of the voting system.

Lula's win was a rebuke for the fiery far-right populism of Bolsonaro, who emerged from the back benches of Congress to forge a conservative coalition but lost support as Brazil ran up one of the worst death tolls of the coronavirus pandemic.

Lula has vowed a return to state-driven economic growth and social policies that helped lift millions out of poverty during his two terms as president.

A former union leader born into poverty, Lula's presidency was marked by a commodity-driven economic boom and he left office with record popularity.

However, his Workers Party was later tarred by a deep recession and a record-breaking corruption scandal that jailed him for 19 months on bribery convictions, which were overturned by the Supreme Court last year.