SINGAPORE, Nov. 21 (Xinhua) -- The 3rd East Asia Summit (EAS) opened here on Wednesday, with the climate change, energy and environment issues topping the agenda.

Sixteen leaders from the EAS will sign a declaration on climate change, energy and environment that is expected to encourage greater attention to climate change, improve energy efficiency, and ensure sustainable development of the region.

Attending the 3rd EAS are "ASEAN Plus Three" countries (Brunei, Cambodia, Indonesia, Laos, Malaysia Myanmar, the Philippines, Singapore, Thailand, Vietnam, China, Japan, the Republic of Korea)and three additional member countries (India, Australia and New Zealand).

The leaders will discuss the impact of global warming and climate change and called on concrete efforts involving the international community in addressing these challenges, said the Joint Communique of the 40th ASEAN ministerial meeting held in Manila, Philippines in July 2007.

ASEAN leaders said in a Chairman's Statement of the 13th ASEAN Summit Monday after the conclusion of the ASEAN Summit that they pledged to deepen cooperation in a wide range of activities, including combating transboundary environmental pollution, and ensuring the conservation and sustainable management of natural resources.

When first held in 2005, the EAS countries decided to intensify regional cooperation in five areas of concern -- finance, education, health disaster mitigation and energy security.