Attempts by German ISP giant T-Online - a unit of Deutsche Telekom - to move into web content have hit a brick wall in the shape of the country's Cartel Office.

The regulator has threatened to block T-Online's purchase of a 37% stake in, the internet offering of daily newspaper Bild Zeitung.

Some €60 million ($52m; £36.6m) of joint investment in the Bild portal are planned by the ISP and publishing giant Axel Springer Verlag, the paper's owner. The deal would allow T-Online to provide its 8.8m subscribers with exclusive access to the site's content.

Issuing a preliminary warning, the Cartel Office cautioned that the agreement would strengthen T-Online's dominance in the web services and access market. However, the warning is not necessarily the final decision, the deadline for which is next week. Until that time, the regulator will continue negotiations with both parties.

Data sourced from: Financial Times; additional content by WARC staff