The US tried yesterday to ensure that future additions to the Kyoto protocol on climate change should avoid committing nations to reducing their carbon dioxide emissions, a move that other countries see as an attempt to undermine the principles of the landmark environmental treaty.

Paula Dobriansky, undersecretary of state, said it was "premature" to begin discussions of what should follow the current stage of the Kyoto protocol, the main provisions of which last only to 2012. She said: "We have programmes and initiatives [to tackle climate change] on the table and we need to concentrate on those programmes, not on future arrangements."