Deutsche Telekom saw sales rise in the second quarter as its US operation continued to offset declines in Europe.
Revenues rose 2.2 percent year-on-year to €17.8 billion in the three months to 30 June.
Sales in Germany fell 3.1 percent to €5.4 billion despite the addition of around 500,000 new mobile customers.
Deutsche Telekom blamed the decline on terminal equipment revenue.
The operator also added just shy of 300,000 fibre broadband customers during the period.
Last month, Deutsche Telekom got the green light from regulators to deploy vectoring technology, which will boost fixed broadband speeds, although it has to provide alternative ways for competitors to access its network.
Tim Höttges, CEO of Deutsche Telekom, said: “We want to maintain the huge momentum in our fiber-optic lines with the Germany-wide vectoring roll-out.
“We are happy to carry competitors on our network – but we will fight for every single customer, that is crystal clear."
In the rest of Europe, sales were down 3.2 percent to €3.1 billion.
Its operating companies in the Netherlands and Poland were hardest hit, with revenues down 12 percent and 11 percent respectively.
Deutsche Telekom blamed “competition-driven price reductions” for the decline in the Netherlands.
Croatia was the best performer with sales up 3.6 percent.
The company was again indebted to the performance of T-Mobile US, where sales grew over 10 percent to €8.2 billion, although growth was 3.9 percent when adjusted for exchange rate effects.
Revenues at the operator’s enterprise arm fell 3.1 percent to €2 billion.
Across the board, Deutsche Telekom’s mobile customer base has increased by 4.3 million since the turn of the year to reach 160.7 million, while the number of broadband lines has grown by 300,000 to 18.1 million.
Adjusted EBITDA rose 8.6 percent to €5.5 billion, but adjusted net profit fell 2.2 percent to €1 billion.