The head of Russia 's state-run gas company OAO Gazprom (GAZP.RS) said Wednesday negotiations with the China National Petroleum Corp. over a 30-year natural gas supply deal were no longer being held up by disagreements on price and that a deal could be reached this year.

"Right now, there are no differences," Gazprom Chief Executive Alexei Miller said, according to Interfax.

He said he hoped the main parameters of the deal would be completed by the summer. "We have a fairly tough time schedule and hope that by June we will be able to sign the basic terms of the contract," he said.

Russia has been looking to Asia for sales as demand falls and competition rises in Europe . Under a preliminary agreement reached late last month, the two sides said they hoped to see Russia begin shipping 38 billion cubic meters of gas a year to China in 2018, with supplies eventually reaching up to 60 billion cubic meters a year.

The two companies have been negotiating for years, but have been wrangling over price.