U.K. Foreign Secretary David Miliband on Monday supported a European Union commitment to further reduce greenhouse emissions to 30%.

The EU has already agreed to cut emissions to 20% by 2020.

"It is existing EU policy to shift from a 20% cut to a 30% cut in the context of an ambitious global deal, and that's what we are committed to maintaining," Miliband told journalists in Brussels.

The EU is ready to make this step should the participants of the UN climate conference in Copenhagen agree on a new international accord to replace the Kyoto Protocol.

The 15th UN climate change conference, a result of two-year international talks on a binding treaty to cut the global emission of greenhouse gases, opened on Monday in Copenhagen.

During the two weeks of talks the governments are to agree on three main climate change points, including urgent measures to tackle climate change, obligations to cut emissions of greenhouse gases and the general view on cutting harmful emissions.

The conference is expected to agree a new international document to replace the Kyoto Protocol on climate change, some elements of which expire in 2012. The document is expected to be ready by summer 2010.

Some experts believe the summit, which puts together about 15,000 participants from 192 countries, is more likely to just outline principles and directions for a post-Kyoto framework.