A Supreme Court justice in Brazil has ruled that President Jair Bolsonaro should be investigated for unproven claims the country's voting system is riddled with fraud.

Justice Alexandre de Moraes added the far-right leader to an ongoing probe on the spread of fake news by his government.

The ruling came after Mr Bolsonaro stepped up his longtime attacks on Brazil's electronic voting system, claiming - without evidence - that it is fraud-plagued and insisting there will be no elections next year as scheduled if it is not overhauled.

The Superior Electoral Court had asked the Supreme Court to issue the ruling, after itself putting the president under investigation for his campaign against Brazil's voting system.

The Supreme Court agreed, finding President Bolsonaro should face investigation for slander and inciting criminal acts for his undocumented claims of massive vote fraud.

Mr Bolsonaro has long criticised electronic voting, introduced in Brazil in 1996.

He has stepped up his attacks in the build-up to the October 2022 elections, insisting on "printable and auditable" paper ballots as a backstop to the electronic system.

Opinion polls place the 66-year-old leader well behind leftist ex-president Luiz Inacio Lula da Silva in the presidential race.

There are fears Mr Bolsonaro could try to use fraud claims to undermine the election if he loses, following in the footsteps of former US president Donald Trump, with whom he is often compared.

Also today, Brazil's incoming presidential chief of staff Ciro Nogueira said the government will relaunch an ambitious social programme to fight hunger and poverty ahead of next year's elections.

President Bolsonaro said he plans to increase the benefits of the popular Bolsa Familia by at least 50% and rename it Auxilio Brasil.

Mr Bolsonaro brought Mr Nogueira, a leader of the centre-right Progressive Party, into his cabinet to shore up support in Congress as he prepares for the 2022 presidential election.

It comes as Brazil reported 40,716 new cases of coronavirus and 1,175 deaths.

The South American country has now registered 20,026,533 cases since the pandemic began, while the official death toll has risen to 559,607, according to ministry data.

Brazil has the world's third worst virus outbreak outside the United States and India and its second-deadliest.