Chief Minister Alf Cannan says it would cost around £30 million to do test drills for gas off the Island's coast.
In the House of Keys this week he was asked for the figures by Douglas Central MHK Chris Thomas.
Mr Cannan said it would take a year and cost up to £7 million to do a 3D survey and around half a million pounds for an environmental impact.
But facing further questions about specific costs private energy company Crogga might face, Mr Cannan said it was to early to say because negotiations are still underway with the government:
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