Israel's attorney general has charged Prime Minister Benjamin Netanyahu with bribery, fraud and breach of trust in connection with three separate cases.
Mr Netanyahu is alleged to have accepted gifts from wealthy businessmen and dispensed favours to try to get more positive press coverage.
He has denied any wrongdoing and said he is the victim of a "witch hunt" by his left-wing opponents and the media.
He has also insisted he will not resign and is not legally obliged to do so.
But the announcement comes amid a political stand-off in Israel following two inconclusive general elections in April and September.
On Wednesday, Mr Netanyahu's rival for the premiership, Benny Gantz, said he had been unable to form a governing coalition with a majority in parliament. He had been given the opportunity to try after Mr Netanyahu had earlier failed to do so.
President Reuven Rivlin asked lawmakers on Thursday to agree on a candidate for prime minister within 21 days and avoid an unprecedented third election in a year.