"From my many talks with Gazprom, my impression is that our Russian partners will fulfil their contractual obligations and want to supply the gas," Oettinger told the Sunday newspaper Welt am Sonntag.
"We are agreed that, in the case of possible economic sanctions — whether from the European or Russian side — the gas sector should not have any priority," the commissioner said.
Russian gas giant Gazprom accounted for around 25 percent of the European gas market, Oettinger, who is German, said to the newspaper.
"I am against scaling back or even cutting our gas links with Russia in the coming years," the commissioner said.
"But we must pursue our strategy of diversification."
Norway and Algeria were also important gas suppliers, Oettinger said, pointing out that 30 percent of supplies came from Europe itself, namely Britain and the Netherlands.
"I would also urgently press Germany to make use of the shale gas option and allow fracking projects," Oettinger said.