Petrol Prices

there is something I don't understand and I wonder if you could ask Gordon a question on my behalf.

We know that cars contribute towards global warming through their emissions.

Petrol in the very recent past was about GBP1.20 a litre, it is now about a pound. So, people were paying substantially more than now.

So, to help towards a reduction in petrol consumption why not put more taxes on the price of petrol and diesel so as to reduce consumption. If we were paying so much more in the recent past then surely there is not a problem!