* Gas supplies to Ukraine cut off on June 16
* European Commission has yet to announce date for talks (Adds Commission comment, context)
MOSCOW, Aug 1 (Reuters) - Officials from Russia, Ukraine and the European Union will discuss gas supplies on Sept. 12, the Interfax news agency quoted Russia's EU envoy, Vladimir Chizhov, as saying on Friday, but EU authorities said they knew nothing about the meeting.
Chizhov was quoted as saying Russia had already made its suggestions known to Brussels for solving a standoff between Russia and Ukraine over gas prices.
A European Commission official said: "We don't know about this date."
European Energy Commissioner Guenther Oettinger has brokered a series of talks involving Russia and Ukraine over how much Kiev should pay Russian natural gas exporter Gazprom for its gas.
The dispute led Moscow on June 16 to halt supplies to Ukraine, which depends on Russia for more than half of its gas needs. Ukraine is also the transit route for up to half of the gas Russia supplies to the European Union, raising the threat of knock-on disruption of supplies.
Oettinger held bilateral talks with Ukraine on the issue in July, but an expected meeting with Russia's energy minister was delayed. (Reporting by Elizabeth Piper in Moscow and Barbara Lewis in Brussels; editing by Lidia Kelly and Jason Neely)