BRUSSELS (Reuters) - Romania’s anti-corruption chief Laura Codruta Kovesi will become the European Union’s first fraud prosecutor after EU countries changed tack and backed her, despite opposition from Bucharest.

FILE PHOTO: Laura Codruta Kovesi, Romania's former chief anti-corruption prosecutor, arrives to attend a hearing at the Section for the Investigation of Criminal Offences in the judiciary in Bucharest, Romania, February 15, 2019. Inquam Photos/Octav Ganea via REUTERS/File Photo

A majority of EU ambassadors voted for her after holding an informal secret ballot, said Marko Ruonala, spokesman for Finland, which currently holds the EU presidency.

EU countries had previously endorsed France’s candidate Jean-Francois Bohnert for the job, triggering criticism from EU lawmakers and other groups.

The EU Council will hold a formal vote in the coming weeks.

Kovesi, who had gained a reputation as a tough anti-graft crusader in Romania before the government sacked her here in July 2018, has already secured support from the European Parliament for the post in the European Public Prosecutor's Office.

Romanian Prime Minister Viorica Dancila told reporters on Wednesday that the Romanian ambassador was mandated to vote against Kovesi’s appointment.

“I will say it again ... we do not support a mandate for Laura Codruta Kovesi,” Dancila told reporters after a party meeting.

EU and U.S. officials have criticized Romania’s ruling Social Democrats for an overhaul of the judiciary that has been seen as a threat to the rule of law, and for watering down anti-graft legislation.

“By choosing Kovesi, the EU is sending a firm message to criminals and the corrupt everywhere, that it is willing to properly defend the EU’s budget,” European Parliament and green lawmaker Saskia Bricmont said.

The EU aims to set up the European Public Prosecutor’s Office next year to tackle graft, VAT fraud and other crimes involving the bloc’s multi-billion-euro joint budget. Twenty-two EU countries have signed up to the project.

Currently, only national authorities can investigate and prosecute fraud against the EU budget in their respective countries.