KIEV, Sept. 9 - Tripartite negotiations on gas between Ukraine, Russia, and the European Commission may take place in Vienna on September 16, Yuriy Vitrenko, the chief advisor to the Naftogaz Ukrayiny board chairman, said on the Ukrainian television channel 24 on Tuesday evening.

"We've talked with Mr. Borchardt [the director of Directorate B for the internal energy market of the European Commission's Energy Directorate-General Klaus-Dieter Borchardt]. He said the working date of the meeting is September 16. Several cities are being discussed, and Vienna has been discussed for September 16," Vitrenko said.