A bid by one of the largest employers in the Highlands to take control of a strategically important part of the Cromarty Firth from the harbour authority that has controlled shipping in the firth since 1973 has been thrown out by the Scottish Government as being legally incompetent.

According to a letter sent to the marine engineering multi-national Global Energy last week by Transport Scotland, Global's proposed Harbour Revision Order (HRO) to wrest control of the Nigg yard from the Port of Cromarty Firth, submitted in December, cannot lawfully be made under section 14 of the 1964 Harbours Act.

Nobody from Global was available to comment as the Sunday Herald went to press, but the chief executive of the Port of Cromarty Firth Bob Buskie said that he was delighted with the outcome. "This is the best decision for the long-term economic wellbeing of communities and stakeholders in the area," he said.

"We will continue to work with Global Energy Group to discuss how the port can further assist the company in achieving its business ambitions."

Despite Buskie's conciliatory tone, the decision by Scottish ministers nevertheless appears to leave open the possibility that Global could make a fresh application to create a new statutory harbour at the mouth of the Cromarty Firth if an application were to be made under section 16 of the act.

It is also understood that Global Energy might have the right to appeal the Scottish Government's decision.

The vice-chairwoman of Invergordon Community Council Tina McCaffery told the Sunday Herald that, although the Scottish government's decision would be welcomed by the community council which had objected to Global's plans, the decision would leave "an awful lot of unhappy people" in and around Cromarty Firth.

Global's application had been made on the promise of bringing more work to the Nigg yard, McCaffery said, and the downturn in the offshore oil and gas sector and consequent thinning out of work in recent months had led many oil workers to support Global's bid.

"On the positive side, there will be no more in-house fighting between the port and Global which was damaging to bringing more work to the area," McCaffery said.

Last year Global had warned that it might withhold £20m of proposed investment in further harbour development at the 700,000 square-metre Nigg yard if its application was unsuccessful.

Last week's development is the latest round in a landmark battle that has pitted the Port of Cromarty Firth against £472 million-turnover Global Energy, which claimed that it could improve its services to potential customers by being in complete control of the Nigg yard.

Global, owned by the charismatic businessman Roy MacGregor, chairman of Ross County Football Club, claimed that its application to create its own port authority would have given it control of around one third of the shipping route in and out of the deep-water Cromarty Firth, which is used by a wide range of traffic from visiting cruise ships in the summer to oil-related boats and tugs towing oil rigs.

According to Global, which is quarter owned by the Japanese marine engineering giant Matsui, a successful application to run the Nigg yard as a separate entity would have allowed it to carry out dredging or other improvement works without having to seek the Port of Cromarty Firth's permission.

This level of control would have allowed Global to offer its customers "fast and efficient berthing that rivals international competitors".

In its official objection to Global's plans the Port of Cromarty Firth had argued that Global's application for an HRO was "flawed" and that an HRO could not be used to create a new port out of an existing one.

The port also claimed that the bid to compulsorily acquire the rights and property of an existing harbour authority without any form of compensation was not in the public interest, particularly as the Port of Cromarty Firth - as a trust port - is run for the public good whereas Global's main interest would have been the interests of its shareholders.

Apart from its objections to the legal process, the Port of Cromarty Firth had also argued that the setting up of a separate port authority within the firth would have impacted on the local economy, the marine environment and could, through the likely rerouting of vessels, have endangered marine safety.

If Scottish ministers had approved Global's plans they would, according to the port, have threatened the inland port of Invergordon's engineering and cruise-liner tourism business.