The chief executive of Caledonian MacBrayne (CalMac), the UK's largest ferry operator, is “stepping down” as it faces ongoing challenges with its fleet.

The company announced Robbie Drummond is stepping down with immediate effect.

It comes just over a week after the chief executive of the state-owned shipyard Ferguson Marine, David Tydeman, was sacked by its board.

Mr Drummond's departure comes after a review by the board of CalMac, which is also wholly owned by the Scottish Government.

In recent years the ageing nature of CalMac's ferry fleet has led to delays and disruption on its routes around the west coast of Scotland.

These problems have been compounded by ongoing delays to two ferries being built at Ferguson Marine in Port Glasgow.

The two ferries, which will ultimately serve routes in the west of Scotland with CalMac, are six years late and will cost around three times the original price of £97 million.

Ministers are also due to make a decision this summer on the awarding of the ferry services contract for the west coast, something which would have a material impact on CalMac as a going concern.

Mr Drummond was previously managing director of CalMac before becoming its chief executive in October 2022.

Last year he was reported to have earned £170,000 in bonuses on top of his £143,000 salary.

His departure was announced in a statement from the company on Wednesday.

It said: "The Caledonian MacBrayne Ltd board takes the responsibility of delivering the Clyde and Hebrides Ferry Service (CHFS) contract extremely seriously.

"It recognises that the island communities served by CalMac have faced real challenges over this past year. These challenges are likely set to continue until new vessels are introduced to the fleet over the coming years.

"In this context, the board wants to strengthen the focus further on operational performance of an ageing fleet, resilience and enhanced dialogue and responsiveness with the customers and the communities CalMac serves.

"As a consequence, the board has reviewed the executive leadership of the organisation to ensure that it is best placed to achieve that during some challenging years ahead.

"As part of that review, current CEO Robbie Drummond is stepping down with immediate effect."

Duncan Mackison, former chief executive of CalMac's holding company David MacBrayne Ltd, has been appointed interim boss until a permanent successor to Mr Drummond is found.