* Deal valued at 618 mln euros, agreed in May 2012
* German cartel office blocked deal last month
* Kabel Deutschland shares down 1 pct
FRANKFURT, March 22 (Reuters) - Kabel Deutschland has filed an appeal against a decision by Germany's competition regulator to block a planned purchase of smaller rival Tele Columbus.
Spokesmen for the German cartel office and Kabel Deutschland on Friday said an appeal had been filed against the blocking of the deal, which was agreed in May last year, for about 618 million euros ($798.8 million) including debt.
They declined to give further details.
Tele Columbus is one of the last big targets left in the country's cable market, which was once one of Europe's most fragmented, with a proliferation of smaller regional players offering television and broadband services.
But private equity firms and companies like Unitymedia, owned by Liberty Global, and Kabel Deutschland have restructured the market by buying up smaller companies to create more efficient larger players.
The German cartel office blocked the deal last month as it found Kabel Deutschland's remedies to get approval inadequate.
Kabel Deutschland's success in the German broadband market has also caught the attention of Vodafone, the biggest mobile operator in Germany.
The UK-based company has hired Goldman Sachs to advise on a possible offer for the company, a person with direct knowledge of the matter told Reuters last month.
Kabel Deutschland shares were down 1 percent by 1400 GMT, underperformimg a 0.1 percent weaker German mid-cap index