Compare petrol price with other countries here.
http://www.k****ij.com/research/petrol.shtml
We already pay too much for petrol in India.
This is because diesel & other agricultural consumables are subsidised by revenue earned from petrol price.
Petrol price up means bus/taxi/transport fare up -> everything dearer
Edit: I don't know why the URL shows ****???
replace **** with S-H-I-T