Inclusive or exclusive of GST

Hi,

We have other income from commission, which we receives from our Joint venture named "X" on providing business. X makes the payment in GBP. and we need to book that amount as commission and has to pay GST.
My question is, can we take it as inclusive of GST or do we need to pay GST from our pocket??
E.g. we received Rs.1,18,000/-(After conversion from GBP)
can we take it as inclusive and pay 18000 as GST or do we need to pay 18% on 118000 i.e. Rs.21,240/-??