President Xi Jinping delivers a speech for the opening day of the World Climate Change Conference 2015 (COP21) at Le Bourget, near Paris, France, November 30, 2015. [Photo/Xinhua]

UNITED NATIONS -- China announced on Friday that it will finalize domestic legal procedures to ratify the Paris Agreement on climate change before the G20 Hangzhou summit in September this year.

The announcement came during a high-level signing ceremony of the landmark pact at the UN headquarters, with a record 171 countries lining up to ink the international accord.

The agreement can enter into force 30 days after at least 55 Parties to the United Nations Framework Convention on Climate Change, accounting for at least 55 percent of global emissions, take the further national step of ratifying it after signing.

A key party to the agreement, China has pledged to cut its carbon emissions per unit of GDP by 60-65 percent by 2030 from 2005 levels, and increase non-fossil fuel sources in primary energy consumption to about 20 percent and peak its carbon emissions by 2030.

"The Chinese people honor their commitments. We will work hard to earnestly implement the Paris Agreement," said Chinese Vice Premier Zhang Gaoli, special envoy of Chinese President Xi Jinping to the signing ceremony.

"We will launch a national emission trade market, substantially increase forest carbon sink. We will put in place a strict accountability system for environmental protection and ensure the implementation of all targets," the presidential envoy said.

Zhang also stressed the importance of international cooperation on the fight against climate change.

"China will take active part in the follow-up negotiations of the Paris Agreement. We will deepen South-South cooperation on climate change," he said.