US leader and wars to dominate G20

Rio de Janeiro - G20 leaders are set to gather in Brazil on Monday for a G20 summit set to be dominated by differences over wars in the Middle East and Ukraine, and implications of Donald Trump's White House return.

Security considerations - always high at such meetings - were elevated further after a failed bomb attack on Wednesday outside Brazil's Supreme Court in Brasilia.

Police were probing two blasts treated as a possible "terrorist act" committed by a Brazilian perpetrator, whose death was the sole casualty.

The summit venue is in Rio de Janeiro, in the city's stunning bayside museum of modern art, which is the epicentre of a massive police deployment designed to keep the public well away.

Brazil's left-wing President Luiz Inacio Lula da Silva will be using the opportunity to highlight his position as a leader championing global south issues while also being courted by the West.

That role will be tested in the months and years ahead as Latin America and other regions navigate the "America First" policies promised by Trump when he becomes president in January.