US President Barack Obama (R) and Chinese President Xi Jinping hold a joint news conference in the Rose Garden at the White House in Washington, September 25, 2015. [Photo/Agencies]

WASHINGTON - President Xi Jinping and his US counterpart Barack Obama outlined their common vision for a global climate change agreement on Friday, including new steps they will take to deliver on pledges made in 2014 to slash their greenhouse gas emissions.

China will launch its national emission trading system in 2017, covering key industry sectors such as iron and steel, power generation, chemicals and building materials, to help contain the country's emissions, said the US-China Joint Presidential Statement on Climate Change.

The emission trading systems, which started its operations from the United States early in 1977 and was followed suit by other Western countries, including Germany, England and Australia, put limits on carbon emissions and open up markets for companies to buy and sell the right to produce emissions.

China's proposed cap-and-trade system would create the world's biggest carbon market.

The joint presidential statement was a highlight of a state visit to Washington by Xi, as the two leaders tackled difficult issues including cyber security.

It built on the US-China Joint Announcement on Climate Change last November, when the United States pledged to reduce its greenhouse gas emissions 26 to 28 perceht below 2005 levels by 2025, while China agreed to cap its rising emissions by 2030.

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