Service Tax on discount received

An assessee pays Rs. 2200 ( 2000 room tarriff + 200 luxury tax ) to a hotel for his business guest's stay.

The hotel gives back a cheque of Rs. 700 i.e. 35% discount on room tarriff to the assessee.

These type of transactions occur frequently during the year due to nature of business of assessee.

Whether the assessee is liable for any service tax on this discount income of the assessee?

If yes, then under which category?