UPDATE 1-EU warns Spain for breach of TV advertising rules

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BRUSSELS, May 6 (Reuters) - The European Commission warned Spain it faced court action for failing to comply with European Union-wide limits on the amount of advertising shown on television.

"Spain has not taken the measures required to ensure compliance with the European limit of 12 minutes of adverts per clock hour," European Media Commissioner Viviane Reding said in a statement on Tuesday.

Reding sent Spain a final warning to comply with the bloc's television rules or risk being taken to the European Court of Justice, which has powers to fine a country and force it to make changes to its laws.

Shares in Spanish television broadcaster Telecinco (TL5.MC) fell after the announcement and were down 2.4 percent at 13.96 euros by 1155 GMT.

The aim of the EU's television without frontiers rules is to prevent audiences having their viewing interrupted by too much advertising and to promote quality television across Europe.

Advertising is key to commercial broadcasters and increasingly harder to come by as channels compete with the Internet for audiences.

"All advertising and teleshopping broadcasts -- including telepromotions, advertorials or however else they are described -- must be taken as counting towards the 12 minutes per clock hour," Reding said.

"To interpret the rule in any other way is to fail to show viewers and citizens the respect they deserve. Rest assured that the Commission will defend their interests," Reding said.

The Commission's monitoring of Spanish television in 2005 and 2006 found the 12 minutes per hour limit was broken regularly.

Reding launched her legal proceedings in July 2007 but Spain said in October it would make no changes, the Commission said.

The 12 minutes per hour rule was reconfirmed in an updated version of the EU rules that came into effect last December. Typically a country has about two months to reply to a final warning from Brussels. (Reporting by William Schomberg; Editing by David Holmes)