SAO PAULO/BRASILIA, Oct 31 (Reuters) – President Jair Bolsonaro had yet to concede defeat in Brazil’s presidential election by Monday afternoon, raising fears the far-right nationalist might contest the victory of his leftist rival, former president Luiz Inacio Lula da Silva.

Tens of thousands of jubilant Lula supporters took to the streets of Sao Paulo on Sunday night to celebrate a stunning comeback for the 77-year-old former metalworker, who governed Brazil from 2003 to 2010. His electoral win follows a spell 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.

Pro-Bolsonaro truckers blocked highways across Brazil to protest Lula’s victory, with some of them calling for a military coup. Truckers, one of Bolsonaro’s key constituencies, have been known to cause economic chaos in top food exporter Brazil when they shut down highways.

The roadblocks, which authorities said had reached 12 Brazilian states in the morning, had not yet disrupted grain exports but could do so if they continued, a key farm state lobby warned.

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

Environmentalists, world leaders and sustainable investors cheered Lula’s victory and his commitment to protect the rainforest and restore Brazil’s leadership on climate change.

Even before he is due to take office on Jan. 1, President-elect Lula will send representatives to next month’s COP27 United Nations climate summit in Sharm El Sheikh, Egypt, allied environmentalist Marina Silva said on Monday.

In his victory speech on Sunday evening, Lula pledged to strongly police illegal logging, mining and land grabbing that have driven the surging destruction of the Amazon rainforest in the past four years under Bolsonaro.

Pitching the contest as a battle for democracy, Lula promised to unite his deeply divided country and celebrated what he called his “resurrection.”

“I will govern for 215 million Brazilians, and not just for those who voted for me,” Lula said at his campaign headquarters. “We are one country, one people, one great nation.”

The Supreme Electoral Court (TSE) declared Lula won 50.9% of votes, against 49.1% 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.

Argentine President Alberto Fernandez hailed “a new era for the history of Latin America. A time of hope and future that begins today.” Fernandez flew to Sao Paulo to meet Lula and they lunched together.

U.S. President Joe Biden moved quickly to congratulate Lula, calling the election “free, fair and credible.” Biden will speak with Lula later on Monday, the White House said.

Congratulations also poured in from other foreign leaders, including China’s Xi Jinping, Russia’s Vladimir Putin, German Chancellor Olaf Scholz and French President Emmanuel Macron.

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

The Bolsonaro campaign did not respond to a request for comment.

“I don’t know if he will call or if he will recognize my victory,” Lula said, in a speech to supporters on Sao Paulo’s Paulista Avenue on Sunday.

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.

Markets braced for a volatile week.

Brazil’s real currency was up around 1% against the dollar after opening about 2% weaker, while the Bovespa (.BVSP) also opened down before rebounding.

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.

(This story has been corrected to mention the correct venue of COP27 summit in paragraph 8)

Reporting by Anthony Boadle and Ricardo Brito in Brasilia, Brian Ellsworth, Ana Mano, Gabriel Araujo and Lisandra Paraguassu in Sao Paulo; Writing by Frank Jack Daniel and Anthony Boadle, Editing by Brad Haynes, Angus MacSwan and Rosalba O’Brien

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