Bild am Sonntag reported that Berlin Airport CEO Hartmut Mehdorn wants the money to build a new runway and complete the project which was meant to open in 2012 and cost around €2 billion.
Despite spending €5.4 billion so far, the airport has been built too small. It will have a capacity of 27 million passengers a year. That compares with 90 million a year at London's Heathrow and 65 million at Frankfurt Airport.
The initial plan was to close Berlin's aging airports, Tegel and Schönefeld, when the new one opened. Between them Tegel and Schönefeld are already dealing with more than 26 million passengers a year and that number is growing.
That number would put the overbudget and long-delayed new transport hub at capacity as soon as it opens.
To address that, Mehdorn wants to build a third runway, Bild am Sonntag reported, saying it had seen documents detailing the latest airport costs.
Mehdorn wants to extend the main terminal building for €1.3 billion and build a third runway for €1 billion.
Other costs include €120 million for extending luggage facilities, €130 million for rebuilding the entrance hall and €20 million for a soundproof hangar to test aircraft engines.
Expanding the current runways and taxiways will cost another €430 million.
Less urgent extra costs in the documents include a 60-metre tall flag pole and a statue of Chancellor Willy Brandt, who the airport is named after, for €500,000 each.
The opposition Green Party reacted with anger to the list. "Madness continues to reign at Berlin Airport," Oliver Krischer, deputy leader of the Greens said. "Whether and how the airport is ever to be operated economically, no one knows."
With huge cost overruns, corruption scandals and no opening date, the airport has long been a national embarrassment.
An airport spokesman declined to comment on the reports.