"We call on the countries that have not signed the protocol or approved the protocol to approve it as soon as possible," foreign ministry spokesman Liu Jianchao told a regular briefing.

Liu made the remark the day after the opening of a 12-day gathering on the Kyoto Protocol in Montreal, Canada.

He did not mention any countries by name in his call for speedy approval of the protocol.

Opposition to the protocol is widely associated with the US government, which demands emissions should be tackled by a voluntary approach, rather than by a legal cap, as is the case with Kyoto's present format.

"We should make efforts to ensure sustainable development and effective environmental protection. The Kyoto Protocol has played an important role in this field," Liu told the briefing.

China is a member of the Kyoto Protocol, the world's most far-reaching environmental treaty, but with a developing country tag it does not have to meet specific targets for cutting emissions.

All rights reserved. copyright 2018 Agence France-Presse. Sections of the information displayed on this page (dispatches, photographs, logos) are protected by intellectual property rights owned by Agence France-Presse. As a consequence, you may not copy, reproduce, modify, transmit, publish, display or in any way commercially exploit any of the content of this section without the prior written consent of Agence France-Presse.