Gst on service rendered to foreign company from india

Export of services‖ means the supply of any service when; (a) the supplier of service is located in India, (b) the recipient of service is located outside India, (c) the place of supply of service is outside India, (d) the payment for such service has been received by the supplier of service in convertible foreign exchange, and (e) the supplier of service and recipient of service are not merely two establishments of a same person.

I think your's is the nature of Export of Services hence NO GST liability is there... I think that you can even claim the refund of the Input credit availed for providing the services to such international firm.. in the RFD 11 form..

Sub section 3 of Sec 16 of Model IGST law provides follow two refund mechanisms in case of export of goods and/or services: (a) a registered taxable person may export goods or services under bond without payment of IGST and claim refund of unutilized input tax credit in accordance with provisions of section 48 of the CGST Act, 2016 (Provisions on Refund). (b) a registered taxable person may export goods or services, on payment of IGST and claim refund of IGST paid on goods and services exported in accordance with provisions of section 48 of the CGST Act, 2016. The detailed conditions, safeguards and procedure would be separately prescribed in this regard vide GST Refund rules.

Regards