PM to seek further emissions cuts

He announced the move after publication of a major international scientific report showing that the Earth is heading for a warmer age at a quickening pace because of human activity.

Mr Brown said he would set out in the next few days various ways in which he believes emissions can be cut.

He is also asking the UK's independent climate change committee to report on whether the target of a 60% reduction in Britain's emissions by 2050 should be even more stringent.

Experts are speculating that he will concentrate on boosting Britain's use of renewable energy, encouraging the use of wind and tidal power.

Europe's leaders agreed in March that a fifth of the bloc's energy should come from renewable sources by 2020, and there has been concern about whether Britain is on course to meet its share of the commitment.

The report, which results from six years of research compiled by the United Nations' Intergovernmental Panel on Climate Change, declares that climate systems have already unquestionably begun to change.

The evidence is in the warming of air and ocean temperatures, widespread melting snow and ice and rising sea levels.

The report will be used by political negotiators meeting next month to begin talks on a successor to the Kyoto Protocol, the action plan for controlling greenhouse gas emissions.

UN experts say a new global plan must be in place by 2009 to ensure a smooth transition when the Kyoto terms expire in 2012.