By Ray Furlong BBC News, Berlin

Kaiserslautern stadium has serious fire risks, the consumer group said

A senior official at Fifa has insisted that 12 German football stadiums to be used during the World Cup this summer are safe.

Walter Gagg, head of stadium security at Fifa, said doubts raised by a leading German consumer group last month were groundless.

He was speaking at a conference in Berlin focusing on security issues connected to the World Cup.

Efforts to combat football hooliganism and terrorism have also been discussed.

The issue of safety at football stadiums has been something of a cloud hanging over the World Cup since last month, when consumer group Stiftung Warentest suggested there were serious shortcomings.

MOST-CRITICISED STADIUMS Berlin Olympic Stadium Gelsenkirchen Veltins-Arena Leipzig Central Stadium Fritz-Walter Stadium, Kaiserslautern Guide to venues

But Mr Gagg rejected those doubts.

"We are convinced that we have 12 wonderful stadia for the World Cup," he said.

"Really, this is a nonsense to make any negative reports about the stadia."

The comments match the generally optimistic tone of the conference dedicated to World Cup security.

Delegates played down the threat of terrorist attack and also voiced confidence that hooligans would not cause trouble at stadiums.

German troops

However, German police have voiced doubts about giant screens being put up to show matches in city centres.

The interior minister for the city of Berlin, Erhart Koerting, supported the idea of having the screens but acknowledged there could be problems, particularly for the biggest games.

"We'll have perhaps 200,000 or 400,000 people, and of course we will have problems there with hooligans from Great Britain; we will have them from the Netherlands, from Croatia - and of course from Germany too," he said.

A further issue of ongoing controversy is the proposal to use German troops for additional security.