does a petrol allowance affect benefits

[midorimum]

the local council have finally agreed to pay me petrol expenses to transport my son to his special needs nursery placement as he couldnt go in a taxi as he is has very poor head control and is frequently car sick.
ive been taking him by myself for 2 years but will now be getting 25p a mile which works out at roughly £26 a week.

does anyone know if this will count as income for child tax credits and housing benefit?

i work for my local council and get paid my fuel allowance (i pick someone up on my way to work that i support) i was also wondering this because i didnt include it in my estimate of earnings, surely it wont make a difference as the money is for petrol and i only get paid for the amount of miles i do (i get paid it in arrears so have to spend the money on petrol first), its not like im profiting from it.