The China-Russia eastern route gas pipeline project under construction in Heilongjiang province. The China section will pass through nine provinces and municipalities to end in Shanghai and will be put into operation in 2018. Song Fulai / Xinhua

Headline deal in a series of energy accords between two countries

Leading Chinese and Russian energy companies have signed a series of asset-swap and supply agreements which will further strengthen the already strong ties between the countries in the sector.

The deals were witnessed by President Xi Jinping and his Russian counterpart Vladimir Putin, who was in the country for China's V-Day celebrations.

The highest-profile signing saw Russian oil giant Rosneft OAO agreeing to take a 30 percent stake in ChemChina Petrochemical Corp, a subsidiary of China National Chemical Corp.

Under the deal Rosneft will increase oil supplies to CCPC to 4 million metric tons a year.

The Russian company is expected to start delivering 220,000 tons of crude a month to CCPC within a year, equal to 48,000 barrels a day.

Rosneft also signed an agreement with China's largest refiner China Petrochemical Corp, or Sinopec, to co-develop two Siberian oilfields.

The accord also gives Sinopec the right to acquire 49 percent of the East Siberian Oil and Gas Co and Tyumenneftegaz, which holds the exploration licences for the Russkoye and Yurubcheno-Tokhomskoye fields, respectively.

Igor Sechin, Rosneft's president, said in total the company signed new agreements worth a potential $30 billion with China.