Exxon Mobil is holding detailed discussions with China's national oil firms on partnerships for a number of resources including unconventional, a top executive said on Monday.

The partnership will cover projects both inside and outside of China.

We are in specific discussions on a number of opportunities that may be of interest to Chinese NOCs (national oil companies) on upstream outside China, Senior Vice President Mark Albers told Reuters in an interview.

Albers said Exxon was very encouraged by China's recent gas price increase and moves toward a more market-based pricing.

It's a clear recognition of the need for gas prices to be sufficient to warm investment, he said.

Albers also said Exxon, the world's largest refiner, is in early studies to expand China's Fujian refining and petrochemical plant, a $5 billion venture in which the U.S. oil giant owns a 25 percent stake.

(Reporting by Chen Aizhu and Shao Xiaoyi; Editing by Ken Wills)