A golden opportunity for Britain to lead the world in humanity's efforts to combat climate change is in grave danger of slipping away. At Prime Minister's Questions yesterday, Mr Blair confirmed that, even if there is to be a Climate Change Bill in next month's Queen Speech, it is likely to be severely watered down. When questioned on the subject, the Prime Minister came out strongly against the idea of annual UK emission reduction targets. Such a pledge, argued Mr Blair, would be irresponsible because it is impossible to predict the UK's energy needs in any given year. An annual target, the Prime Minister stressed, would be an unacceptable restriction on the nation.

What Mr Blair seems to be saying here is that we should trust him to get on with reducing carbon emissions in his own way. But the time for such unquestioning faith is over. What we need now is accountability. The stark fact is that, for all the Government's bold rhetoric on global warming, the UK's carbon emissions are rising, not falling. The Prime Minister points to his government's ambitious target of cutting emissions by 20 per cent by 2020 (and by 50 per cent by the middle of the century) as if merely outlining a distant target is evidence of serious activity. Yet Mr Blair will have left office long before he can be called to answer for these promises.

Without the discipline of annual targets, Britain's emission levels will continue to rise. That is why the primary demand of our climate-change manifesto today is for annual emission reduction targets, with the results to be monitored by an independent body. That is the only way to compel our leaders to take serious action.

Another central proposal in our manifesto is for a hefty rise in environmental taxes. There has been a good deal of debate in recent months about whether green taxes will raise enough revenue to cover tax reductions in other areas. But this has missed the point. The goal of these taxes is to discourage people from damaging the environment through unnecessary journeys and flights. This is the criterion by which we should judge such levies. Such an approach has been successfully used against polluters in the past. The Clean Air Acts in 1956 and 1968 worked on this principle. The result was a significant improvement in the quality of air in Britain. Green taxation can have the same effect if rolled out on a global scale. And Britain should take the lead.

This process will inevitably involve pain. The public will pay more to drive. The cost of flying will rise. But we should not lose sight of the gains our society will reap too. There will be new jobs as the renewable-energy industry expands. As Scandinavian countries have proved over the past decade, green economic growth is perfectly possible.

There is political space for the Government to act now. The Conservatives and the Liberal Democrats are both calling for annual reductions in emissions. A cross-party consensus is possible for the first time, if the Government could only find the courage to grasp this chance.

An opinion poll this week showed that two-thirds of the population is now concerned about climate change. And only 4 per cent of voters think Mr Blair has made effective progress on the issue. Public disquiet is growing. The message is getting through. Yet the Government looks out of touch.

The time for prevarication and warm words is over. Difficult decisions can be avoided no longer. The Independent's climate-change manifesto proposes measures we believe are necessary to safeguard the future of our way of life. The responsibility for action now lies with our leaders.