Hungarian prosecutors have charged one of the country’s members of the European Parliament with spying for Russia.
Bela Kovacs, 57, from the nationalist Jobbik party, has denied the charged.
A Hungarian inquiry began in 2015 after the European Parliament lifted Mr Kovacs’ immunity.
Prime Minister Viktor Orban, leader of the right-wing Fidesz party, has warm relations with Russian President Vladimir Putin.
A Fidesz party spokesman said the charges were a “serious European-level affair” against “a Jobbik politician”.
Jobbik said it “welcomed” the case after it had been “dragged out for three-and-a-half years by the Fidesz state machinery”.
Since Mr Orban’s re-election in 2014, Jobbik’s popularity has grown. Opinions polls put the party in second place behind the ruling Fidesz party.
Mr Kovacs has described the charges as “deliberately timed” to target Jobbik ahead of elections that are expected to be held in April 2018. But he said he was resigning from the party in order to prevent damaging it ahead of the elections.
“I am very happy that we finally made it to this point and I can clear my name in court and put an end to this saga,” Mr Kovacs told Reuters news agency.
Prosecutors said the charges against Mr Kovacs included “spying” against EU institutions, using forged documentation and fiscal fraud.
If convicted, Mr Kovacs could face between two to eight years in prison.