GENEVA - More than 140 countries have agreed on the first global treaty to cut mercury pollution through a blacklist of household items and new controls on power plants and small-scale mines, the United Nations said yesterday.

The legally-binding agreement aims to phase out many products that use the toxic liquid metal such as batteries, thermometers and some fluorescent lamps, through banning global import and exports by 2020.

The treaty will require countries with coal-fired power plants such as India and China to install filters and scrubbers on new plants and to commit to reducing emissions from existing operations to prevent mercury from coal reaching the atmosphere.

"We have closed a chapter on a journey that has taken four years of often intense but ultimately successful negotiations and opened a new chapter toward a sustainable future," said Fernando Lugris, chair of the negotiations.

The deal also includes measures to reduce mercury use in small-scale gold mining, although stopped short of an all-out ban.

The Minamata Convention on Mercury needs ratification from 50 countries and is expected to be formalized later this year. It requires governments to draw up national rules to comply and could take up to five years to take effect.