Tony Blair and the UK are hoping that tough sanctions on CO2 emissions will pave the way for China and the US to do the same. Included in the bill is an emissions cap and the creation of seperate governing body that will reset the cap and police it every 5 years. This is most likely a strategic move by Blair in preparing for the upcoming election, to gain favor in domestic matters while foreign policy has been unpopular.
Also, last week the EU Union as a whole agreed to produce 20% of its energy through renewable resources, decreasing emissions and have less environmental impact.
The EU uses am emissions trading system that assigns quotas outlining the maximum emissions alloted and can buy and sell the allowances. The US on the other hand does not use the trading system but puts a cap on emissions.
http://www.delawareonline.com/apps/pbcs.dll/article?AID=/20070318/BUSINESS/703180332/1003