The tax increase hit **petrol users** hardest because most northern vehicles ran on petrol, not diesel. [fact]
The tax on petrol in the north was raised to the rate currently applied in the south, causing petrol prices in the north to double. At the same time the tax on diesel fuel was reduced and also import duties on alcohol and cigarettes to bring the northern prices into line with those in the south. These latter measures were expected to offset the increases in petrol prices. Unfortunately, however, for reasons which are difficult to understand, the government failed to realize that almost all motor vehicles in the north use petrol and not diesel oil. Northerners found little comfort in the reductions in alcohol and cigarette prices which they regarded in the circumstances as derisory.
I.M. Lewis, I. M. Lewis, A Modern History of the Som…, loc. 839