Urd input tax- karnataka vat

Sir,

I am a registered dealer under KVAT. I purchase goods from Unregistered dealer and pay URD tax @ 5%. I have interstate sales which is chargeable @ 2% CST. can I set off the tax paid on URD purchases against CST collected?

URD Purchases Rs 100  Tax paid on URD  Rs 5

CST Sales Rs 110      CST Collected Rs 2.20

Can I claim the refund of Rs 2.80?