Russia, Ukraine and the EU plan to meet next week for talks to resolve a gas dispute between Kiev and Moscow, European Energy Commissioner Guenther Oettinger said on Monday. "On Monday (May 26), a meeting is scheduled with Ukraine, Russia and the Commission," he said on ARD public television before meeting Russian Energy Minister Alexander Novak and the vice president of Russian energy giant Gazprom, Alexander Medvedev, in the German capital. After the meeting he again confirmed that all sides were "working toward" scheduling more talks for next week. The date would be "subject to confirmation by the various parties", a European Commission spokeswoman in Brussels told AFP. She added that the meeting could take place in Berlin. Gazprom has warned Kiev it could suspend its gas deliveries on June 3 if the former Soviet republic does not settle by then its bill for June, worth $1.66 billion, Moscow has started demanding pre-payments for gas shipments to Ukraine under new rules introduced in response to the Ukraine crisis. This threat has raised concern in the European Union, which imports a quarter of its gas from Russia, nearly half of which flows via Ukraine. Because of its financial difficulties, Kiev has accumulated $3.5 billion in unpaid gas debt to Russia. The EU is trying to mediate between Kiev and Moscow to resolve the conflict. "We will do everything in the next few days to clarify the issue of unpaid bills and, through aid, allow Ukraine to pay the bills at an appropriate price," Oettinger said Monday. The first such three-way talks were held on May 2 in Warsaw but failed to end the dispute.