Nissan has withdrawn its sponsorship from the Radioshack-Nissan-Trek WorldTour cycling team with immediate effect and will withdraw its funding from the end of 2013.

The team, formed last year from a merger of Flavio Becca’s Leopard-Trek team and Johaan Bruyneel’s Radioshack outfit, had been beset by problems in 2012.

General manager, Bruyneel, was implicated in USADA’s investigation into organised doping at the Lance-Armstrong led US Postal team he had managed.

The Belgian, who subsequently managed Armstrong at Discovery Channel, and during the Texan’s comeback with the Astana and RadioShack teams, strenuously denies USADA’s allegations.

He is due to appear at a public arbitration hearing in the new year.

Bruyneel parted company with Radioshack-Nissan-Trek “by mutual agreement” in October. He had been replaced by Luca Guercilena as team manager for the Tour de France on the eve of the race.

Frank Schleck was withdrawn from the Tour after failing a test for the banned diuretic Xipamide. Schleck continues to protest his innocence.

Now Nissan has confirmed that it has reached an agreement with the management of RadioShack-Nissan-Trek for its immediate withdrawal as sponsor, “while enabling the team to continue competing in the upcoming 2013 season.”

The departure is similar to that managed by Rabobank, which will fund Blanco Pro Cycling in 2013, without its name on the jersey.

Rabobank’s CFO, Bert Bruggink, announced in October that his board’s decision to withdraw its backing had been directly influenced by the USADA report.