A HIGHLAND port authority has vowed to fight plans by a private firm to take control of a major waterway.

Cromarty Firth Port Authority (CFPA) says the move by the Global Energy Group to create a private harbour authority would "kill stone dead" the lucrative cruise liner trade on the firth.

It has been confirmed that ministers would consider the firm's application in terms of the requirements of the Harbours Act 1964.

The Global group is owned by Highland businessman Roy MacGregor, chairman of Ross County FC.

The move by Global could see it gain control over half the channel at the entrance to Cromarty Firth, at the former Nigg fabrication yard which Global largely owns.

For the last four decades the waterway, and the rest of the firth, has been under the control of the CPFA. All shipping on the firth has to pass through the area, from liners to tugs towing oil rigs.

The authority says Global, in which Japanese corporation Mitsui & Co has a 25 per cent stake, is preparing to seek Scottish Government permission for the highly controversial move.

Chief executive of the CFPA, Bob Buskie, said: "It would be wrong for a large part of the access to the Firth, a strategically important national asset, to be in private hands."

"We have huge concerns what these plans would mean for the cost of access to the firth, for navigation and for health and safety and natural environment in these waters."

Global, who Mr Buskie said had written outlining the company's plans to establish the private port, did not respond to a request for comment.