* Tele Columbus shares depressed as losses mount
* Speculation focuses on minority owner United Internet
* CEO seeks tough conditions on Vodafone-Liberty deal
By Nadine Schimroszik
BERLIN, Sept 5 (Reuters) - Tele Columbus is focused on building its business and boosting internet services to 3.6 million customers after problems integrating recent acquisitions, as Germany's third-largest cable TV provider seeks to stay independent.
Speculation over the future of Tele Columbus has persisted since United Internet, the German internet and mobile services provider, accumulated a 28.5 percent stake in 2016. United Internet has declined to comment on its plans.
Shares in Tele Columbus, which faces mounting losses and a cut its outlook for the year, have fallen by more than 70 percent this year, depressed in particular by a delay to the publication of its mid-year results.
"It is not our goal to be taken over," the company's chief executive Timm Degenhardt told Reuters. He declined to elaborate on his defence strategy for Tele Columbus, whose market capitalisation has fallen to 330 million euros ($382 million).
In an effort to refinance its debts, Tele Columbus issued new bonds worth 650 million euros in May, but holders are nursing sizable losses on the notes.
Half-year results showed that Tele Columbus had posted a loss of 31 million euros, up threefold due to rising costs and falling sales in its TV business.
The company also had to cut its forecast for earnings before interest, taxation, depreciation and amortisation (EBITDA) for the year to 235 million euros, from an earlier 265-280 million.
Degenhardt's efforts to turn around Tele Columbus coincide with Vodafone seeking approval to take over key European assets of Liberty Global, including its German unit Unitymedia, in a $21.8 billion deal that would strengthen the company's market lead in Germany.
Antitrust regulators should impose "strict conditions" on the deal, which would create Germany's only cable TV provider with nationwide coverage, to ensure that its smaller competitors can survive, he said.
Other market players have said Vodafone should be required to open up 'last mile' access to German households to its competitors. ($1 = 0.8648 euros) (Reporting by Nadine Schimroszik Writing by Douglas Busvine Editing by Alexander Smith)