BERLIN (Reuters) - The German government said on Thursday it was closely watching the latest doping scandal in cycling and urged the sport to get its house in order before September's world road race championships in Stuttgart.

A steering group has been formed, including the international and German cycling associations and anti-doping organisations, to draw up a new testing regime for the championships, an interior ministry spokesman said at a regular news conference.

"We are very closely watching developments, with justified concern considering the Road World Championships in Stuttgart at the end of September," the spokesman said.

"Federal, state and local governments have contributed a not insignificant amount of public tax money," he added.

"One thing is clear: the world championships in Stuttgart must be a new start. Things cannot continue like this."

German cycling was thrown into fresh turmoil on Wednesday when state TV shelved coverage of the Tour de France in response to T-Mobile rider Patrik Sinkewitz testing positive for elevated levels of testosterone.

State broadcasters ARD and ZDF said they were halting coverage of cycling's most prestigious race, which is watched by more than a million Germans, until the Sinkewitz case was resolved.

The latest development follows a string of doping confessions by and allegations against riders associated with T-Mobile and its predecessor Team Telekom.

"We are observing closely what happens at the Tour de France, and also the doping regime used there," the German interior ministry spokesman said on Thursday.

Stuttgart hosts the world road race championships from September 25-30. As well as the German government, sponsors for the event include the Skoda unit of German carmaker Volkswagen and Tissot, a brand of Swiss watchmaker Swatch Group.