WASHINGTON, July 14 -- The head of International Energy Agency (IEA) on Monday called for more cooperation between her organization and emerging economies outside the IEA as the latter has become ever more important in global energy demand.

"The world has changed dramatically since the founding of the IEA, driving us to evolve and to develop our capability accordingly," said Maria van der Hoeven, executive director of the IEA at the opening of an annual energy meeting held by the U.S. Energy Information Administration (EIA).

"Demand pattern has shifted. The IEA members once accounted for around three quarters of global demand and now account for less than a half. This requires that we engage more closely with emerging economies like China and India, increasingly the engine of the global demand," van der Hoeven said.

To strengthen such cooperation, van der Hoeven said the IEA is "exploring the social membership for several of these countries," which is "a shared value and interest here in Washington."

"I was very pleased to see last week that China and the U.S. signed preliminary agreement to cooperate on strategic petroleum reserves," she said.

The IEA was founded in 1974 aiming to prevent industrial countries from suffering again the oil crisis that happened in the early 1970s. In 2014, Estonia joined the IEA to become its 29th member state.