Brazil's top prosecutor charged President Michel Temer with bribery on Monday, plunging Latin America's biggest country into what could be prolonged new political turmoil.
The bribery charge filed by Prosecutor General Rodrigo Janot swept Temer into the forefront of a giant graft scandal that has engulfed Latin America's biggest country over the last three years.
Although several past Brazilian presidents and scores of other politicians are currently being investigated for corruption in the "Car Wash" probe, Temer is the first leader in the country's history to face criminal charges while still in office.
Temer acted "in violation of his duties to the state and to society," Janot wrote, citing "abundant" proof that the president received bribe money.
For Temer to go on trial, the lower house of Congress must first approve Janot's charge by a two-thirds majority. Temer would then be suspended for six months for the trial.
Janot is also probing Temer for alleged obstruction of justice and membership of a criminal group. He could file those charges at a later date, guaranteeing a sustained legal assault.
However, Temer's aides say they are confident he has sufficient support in Congress to get the charges thrown out.
In his first comments since returning from a trip to Russia and Norway, the president was defiant.
"There is no plan B," he said at a ceremony to sign a new bill in the capital Brasilia. "Nothing will destroy us - not me and not our ministers."
The Eurasia Group risk consultancy said there was a 70 percent chance of Temer lasting to the end of his term through 2018.
"Temer still enjoys enough support in congress (at least one-third, or 172 votes) to defend himself against the charges," Eurasia Group's analysis said.
"For most lawmakers, while there are now fewer incentives to openly support the Temer government, there are even fewer incentives to remove Temer from his seat."
Temer's latest approval ratings are just seven percent, lower than his deeply unpopular leftist predecessor Dilma Rousseff, whom he replaced last year after she was impeached by his center-right congressional allies for breaking budgetary rules.
He took over promising to restore political stability and to steer Brazil out of its deepest recession in history with market reforms.
Yet the political capital he needs for those reforms, including the hugely unpopular proposal to cut back generous pensions and to free up labor laws, is rapidly slipping away.
Currently, the lower house of Congress is lukewarm about bringing him down. There is no clear candidate to take his place on an interim basis before scheduled elections in October 2018, and many of the major figures in Congress are themselves battling corruption allegations.
But Janot's decision to separate the charges, filing them piecemeal, could drag out the crisis and weaken Temer's base, making congressional approval for a trial more likely.
A long simmering scandal could also have the potential to stir up public anger in the streets.
The bribery charge is linked to the arrest of a close former presidential aide with a suitcase stuffed with cash that prosecutors say was part of payments from JBS meatpacking executives to Temer.
In a filing with the Supreme Court, Janot accused Temer of receiving a 500,000-real (about $150,000) bribe.
Equally explosive is the allegation that Temer approved of a plan with Joesley Batista, owner of JBS parent company J&F, to pay hush money to a politician jailed for corruption.
Batista secretly recorded Temer allegedly discussing the hush money and gave the recording to prosecutors in a plea bargain to secure leniency in his own corruption case.
In a further sign of Temer's weakening position, an important figure in his ruling coalition, former president Fernando Henrique Cardoso, called for him to step down and help Brazil hold new elections as "a gesture of greatness."