A multi-million pound project to extract tin from seabed deposits off the Cornish coast will "inevitably" hit local fishermen, it has been warned.
Marine Minerals Limited (MML) is targeting metal deposits which have been washed out to sea during historic mining activities in West Cornwall.
It is currently taking samples along the coast from St Ives to Perranporth to establish whether extracting the tin, believed to be worth millions of pounds, is commercially viable.
Concerns have already been raised about the lack of consultation over the survey work.
Eddy Derriman, head of the Cornwall Inshore Fisheries and Conservation Authority, said that the initial work was "unlikely" to affect fishermen. But, he warned in a letter to St Ives Liberal Democrat MP Andrew George: "If the project comes to fruition and the mining activity starts, then inevitably they will be affected on a practical front and will be required to shift their gear and potentially may be affected if there is any local impact on fish/shellfish stocks."
A spokesman for MML said it was already in discussions with fishing groups while it was working on environmental studies of the project's possible impact.
He said: "It is a very important part of our study to understand the concerns of the fishing industry and to ensure those concerns are fully investigated." Mr George said the scheme could generate jobs but the views of both fishermen and conservationists must be considered.