“Some people say that it is nepotism, but that’s for the Supreme Court to decide. It is not nepotism, I would never do that,” Mr Bolsonaro said on a live social media broadcast on Friday.
The president revealed that he was considering nominating his son, a congressman representing Rio de Janeiro, for the post on Thursday. The 35-year-old said he would accept the job if offered.
Despite insisting no decision had yet been made, Mr Bolsonaro ticked off a list of his son’s qualifications for the post: “My son Eduardo speaks English, he speaks Spanish. He’s travelled all over the world. He’s friends with Donald Trump’s children.
“My understanding is that he could be a qualified person and would be the perfect message to Washington.”
Brazil's supreme court barred nepotism in 2008. The initial findings of a study carried out by the president’s office showed that top-ranking political appointments, like those of ambassador, would not legally constitute nepotism.
The president’s comments set off an uproar among opposition MPs. Senate opposition leader Randolfe Rodrigues tweeted: “It’s absurd that he’s even being considered.
“Bolsonaro wants to govern in his backyard, extending [the government] to his family ... Eduardo Bolsonaro’s nomination for ambassador is unacceptable.”
He called the move “unprecedented in the history of Brazilian diplomacy” and said he was “certain” the Brazilian Senate would not approve the nomination.
Congressman Ivan Valente of the left-wing Socialism and Liberty Party said the nomination would be unethical. “This is a complete mess. An international embarrassment,” he tweeted.
Eduardo is the third child of the president, who has four sons and a daughter from three marriages, and has already advised his father on foreign affairs.
When asked by reporters about his qualifications for the position, he said he had been in a foreign exchange programme where he “fried hamburgers in the United States, in the cold in Maine”.
A 2017 YouTube video shows him standing in front of a Popeyes chicken counter recounting his time in the US between 2004 and 2005.
His appointment would need to be approved by the Senate Foreign Relations Committee before passing to the full upper house for confirmation.
Additional reporting by agencies