The heavyweights of world trade, including the United States, China and Japan, meet in Geneva this weekend to establish a list of environmentally friendly products for which tariffs can be eliminated or reduced.
The green products include solar panels, wind turbines and air quality monitors "that can help achieve environmental and climate protection goals," the World Trade Organization said.
EU Trade Commissioner Cecilia Malmstroem is expected at the WTO talks on Saturday along with senior officials of 17 countries, including US Trade Representative Michael Froman.
The officials hope to finalise an accord on Sunday but nothing is guaranteed, a source close to the WTO said.
Talks on the Environmental Goods Agreement began in July 2014, based on a proposal at the World Economic Forum in Davos six months earlier.
Malmstroem said some 300 environment-related products would be considered at the Geneva talks.
Over $1,000 billion (940 billion euros) worth of goods in this sector are traded every year, the WTO said.
If a deal is reached this weekend, countries will next year establish a list of reduced tariffs for each product, a WTO spokeswoman said on Friday.
The WTO said the benefits of any agreement would be extended to all of its members.
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