Brussels welcomes Beijing and Washington's commitments in reducing carbon emission in post-2020 period, saying the global efforts have been scaled up to reach an international deal in Paris next year.

European Commission President Jean-Claude Juncker and European Council President Herman Van Rompuy swiftly responded within a few hours after Beijing and Washington announced their agreement during President Barack Obama visit in China.

"We welcome the announcement today by the Presidents of the United States and China on their respective post-2020 actions on climate change. This comes ahead of the G20 Summit in Brisbane, and well in advance of the Conference of the Parties 21 in Paris next year," they said in a joint statement.

They also say announcement shows that the call by EU Leaders on 24 October to other countries to come forward quickly with their intended greenhouse gas emissions reduction targets is being answered.

The European Union agreed in October ambitious targets for 2030 with a legally binding reduction of CO2 emissions of at least 40 percent, increases of renewable energy and energy efficiency of at least 27 percent and a boost of the internal European energy market through a boost of interconnection.

"The announcements to date cover around half of the global emissions. We urge others, especially the G20 members, to announce their targets in the first half of 2015 and transparently," the European leaders say.

"Only then we can assess together if our collective efforts will allow us to fulfil the goal of keeping global temperature increases well below 2 degrees Celsius."

They also say in the multilateral UN negotiation process, Lima is the next milestone and they look forward to engaging with all our partners.

"The clock is ticking. It's time to move to action," the statement was cited.