Truckers who support Brazil's outgoing President Jair Bolsonaro escalated their protests on Monday, blocking roads throughout the country in actions that could affect exports in one of the world's top food producers and cause wider economic chaos.

Bolsonaro lost Sunday's election to leftist former President Luiz Inacio Lula da Silva, but has yet to concede defeat. He will not publicly address his defeat until Tuesday, a cabinet minister said on Monday evening, amid doubts over whether the far-right nationalist will accept Lula's victory.

Video footage showed some truckers at roadblocks calling for a military coup to prevent Lula becoming president, as protests spread from Mato Grosso and Santa Catarina to Parana, Sao Paulo, Minas Gerais, Goias and Bahia.