Duty against Subsidy

If on Import of goods to India from Outside India (Say U. K) the U. K govt. will give subsidy to Vendor of U. K suppose on per unit basis then that vendor can reduce the price per unit of the exported goods (from U. K) to the extent of subsidy received on those goods. since that would cause an adverse effect on Indian Industries, hence Indian Govt. have introduced Countervailing duty on import of such kind of articles so that price of such goods can be increased. however such duty can't exceeds amount of subsidy

Thanks. But this is a bit risky for govt. Bcos U.K will not inform India before sending good that on this we have given subsidy. Not inform Bcos they want to promote exports. So is it that duty will be imposed if value declared indicates subsidy

i think so Customs department will came to know about subsidy through import price of such articles which will be cheaper than price of like kind of articles in India or price of like non subsidized articles imported from other countries.