Leaders from 16 major economies have been invited to a “preparatory session” on April 27-28 in Washington to “help generate the political leadership necessary” to achieve an international pact to cut greenhouse gas emissions later this year, it said in a statement.

It said the meeting would spur dialogue among developed and developing countries about the issue, “and advance the exploration of concrete initiatives and joint ventures that increase the supply of clean energy while cutting greenhouse gas emissions.”

The major economies include: Australia, Brazil, Britain, Canada, China, the European Union, France, Germany, India, Indonesia, Italy, Japan, Korea, Mexico, Russia, South Africa and the United States.

Denmark, which is hosting a U.N. meeting at the end of this year to forge a pact that would take over from the Kyoto Protocol, and the United Nations were also invited.

The group’s preparatory sessions would culminate with a major meeting on the subject in Italy in July.