The Swiss government has appointed a special prosecutor to consider criminal charges against Fifa president Gianni Infantino, and its own top lawyer, federal prosecutor Michael Lauber.

The move caps months of controversy surrounding Mr Lauber, who has almost untrammelled power over all criminal investigations in Switzerland, and his handling of his agency’s years-long probe into corruption in world football.

Revelations last year that Mr Lauber had held numerous secret meetings with Mr Infantino to discuss his officials’ sensitive investigations against football’s governing body have all-but derailed the chances of those in Fifa suspected of corruption being successfully brought to trial in Switzerland. The body is headquartered in Zurich.

Swiss parliamentary authorities officially forwarded a dossier of three criminal complaints, which relate to the relationship between Mr Lauber and Mr Infantino, to the inspectorate which oversees Mr Lauber, the AB-BA, on Monday.

The complaints were accompanied by a formal request for extraordinary legal authorisation to look into his activities, and those of Mr Infantino, independent of the country’s existing investigatory structure, over which Mr Lauber presides.

In a statement on Friday, the AB-BA said it had approved the parliamentary request and appointed Stefan Keller, a former military judicial investigator and professor of law, as special prosecutor.

Under Swiss law, Mr Keller must independently decide whether the complaints have enough substance to be taken forward. If so, he will apply to the Swiss parliament for a vote to lift Mr Lauber’s federal immunity.

“The AB-BA notes that the appointment, as is customary in cases of this kind, will for the time being serve only to review the criminal complaints filed,” the supervisor stressed. In a short statement, Mr Lauber’s office said it had “taken note” of Mr Keller’s appointment but had nothing further to add. Fifa said it welcomed the “expeditious appointment” of the special prosecutor. “Fifa has been fully and transparently co-operating with the authorities and will continue to do so,” it said.

The body dismissed the criminal complaints that underpin the prosecutor’s appointment as based on “anonymous complaints” and said Mr Infantino had been the target of such unfounded accusations in the past. 

Mr Infantino was elected Fifa president in 2016 on a promise of cleaning up the world’s most popular sport. But he has drawn criticism for his attempts to curb the independence and strength of internal ethics bodies.

Emails leaked earlier this year, meanwhile, showed that Mr Infantino had intended to lobby Mr Lauber to drop investigations into his conduct while he was legal affairs director at Uefa, the governing body of European football.

Despite revelations over the Fifa case, Mr Lauber was re-elected by parliamentarians for a third four-year term in office only last September.