The European Commission is to file suit against the UK after government officials failed to act against the controversial Phorm advertising system.

The Commission said that by not taking action against telcos that use the advertising platform, UK government authorities ran foul of EU privacy and data protection laws.

"We have been following the Phorm case for some time and have concluded that there are problems in the way the UK has implemented parts of EU rules on the confidentiality of communications," EU telecoms commissioner Viviane Reding said in a statement.

"I call on the UK authorities to change their national laws and ensure that national authorities are duly empowered and have proper sanctions at their disposal to enforce EU legislation on the confidentiality of communications."

Phorm has drawn sharp criticism over its advertising platform, which logs user traffic patterns to offer targeted ads. Telcos argue that the system increases the quality and value of advertisements, while opponents call it a blatant invasion of user privacy.

The Commission said that it decided to take action in the case after receiving complaints from UK consumers and officials over the government's handling of Phorm. The EU said that the UK has had since July 2008 to explain its position.