India and China, two most sought-after customers of the Organization of the Petroleum Exporting Countries (Opec), have put in place a mechanism to figure out ways to fight crude oil volatility and teamed up for other energy issues in global markets. The two countries have set up a joint working group that would identify subjects of cooperation in the energy sector, including ways to rein in global oil prices. The group, set up a month ago, will be co-chaired by a joint secretary in the oil ministry and his Chinese counterpart. China and India, second- and third-largest oil consumers, respectively, have been meaning to form a joint front for more than a decade to assert their weight in the oil market, dominated by a producers' cartel, Opec. In 2005, then oil minister Mani Shankar Aiyar had proposed the idea but it didn't make much headway. The countries, however, partnered in some upstream projects in the last decade after engaging in fierce competition for oil and gas blocks in Africa and Asia. Petroleum & natural gas minister Dharmendra Pradhan revived cooperation talks with China last year. He also mooted the idea of Japan, South Korea, China and India - the top four Asian oil importers - forming a buyers' bloc. Although the two nations stand to benefit from joint action, it may not be easy to collaborate on most strategic matters. The latest opportunity to stand together on Iran sanctions was lost after China and India, top importers of Iranian oil, failed to jointly strategise and act.