Christophe Lemaire's debut as a fully licensed jockey in Japan is on hold for 30 days with the rider banned for using Twitter at Hanshin racecourse.

Lemaire, winner of the 2011 Melbourne Cup on Dunaden, was due to have his first rides at the track under his new licence.

But stewards found he broke the rules when he did not switch off his phone on Saturday evening and retweeted an acquaintance's post.

The Japan Racing Association's Paris representative Fumi Tsuruoka said there was no right of appeal.

"All the jockeys who have some engagement to ride in JRA races are required to check in the Jockey's Quarter at the racecourse or Miho/Ritto Training Centre by 9pm on the day prior to the race day," Tsuruoka said.

He said jockeys were banned from contacting anyone until after they had ridden in their final race.

The stewards ruling said Lemaire's conduct "was deemed (to) neglect of the care duty as a jockey" under JRA rules.