Wellbeing economy secretary Neil Gray has said he is unable to explain the depths of delays expected in the completion of two ferries at the centre of Scotland's ferry fiasco after safety regulators demanded new design changes before any approvals are given.

Among the issues to be resolved is the installation of additional staircases on Glen Sannox and Hull 802, now named Glen Rosa in order to satisfy the Maritime and Coastguard Agency (MCA), which is responsible for implementing British and international maritime law and safety policy.

The work means planned sea trials of the Glen Sannox have been delayed until the first quarter of next year.

CalMac had expected Glen Sannox to be handed over in December 2023, and Glen Rosa in December 2024. They say that once handed over there will be a two month period where there will be crew familiarisation and network trials.

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It has raised new fears over not just whether Glen Sannox will be available for the start of the 2024 summer season - but whether it will be passed fit to sail at all.

Mr Gray has told the Scottish Parliament Net Zero, Energy and Transport Committee that he was unaware of any issues when he gave his last parliamentary update, understood to have been in May.

The Herald:

He said that the MCA decision making was "pretty fundamental" and he did know whether hopes of Glen Sannox being ready by the spring of next year can be met.

David Tydeman, chief executive of the nationalised Inverclyde shipyard firm had previously stated he was optimistic that Glen Sannox should be available to passengers in spring 2024.

The delayed second vessel, Glen Rosa which which was supposed to be online in the last reschedule in the autumn of 2024 having already been delayed to the end of March 2024, had been pushed back to November, 2024. The contract backstop was stated as being at the end of December 2024.

Both vessels were due online in the first half of 2018, with one intitially to serve Arran and the other to serve the Skye triangle routes to North Uist and Harris, but are at least five years late, with costs expected to be quadruple the original £97m contract. It has been confirmed that both are now to serve Arran.

The Herald:

Pushed by the committee convener Edward Mountain over when Glen Sannox would be in service, Mr Gray said that the MCA involvement was no "minor thing" and that it would be "inappropriate" for him to intervene.

He said: "The MCA’s decision making on the safety of crew escape from the ships – this is pretty fundamental to whether or not the design of the ferry allows it to sail. It’s not an inconsequential matter.

"And so, I hope, obviously, that the last update, in terms of spring, can be met, but until those discussions with the MCA are concluded I cannot give any further definitive update. I think it would be unfair to suggest that the MCA’s decision making is anything other than critical to the delivery of these ferries”.

He said Mr Tydeman would give an update in due course "and that's got to be based on decisions that are still to be taken by the MCA as to whether or not the mitigations that are going to be taken on the design of the ferry are going to be appropriate for the MCA to pass those ferries as being safe to operate. So these are discussions that are ongoing, which is why I cannot give a date.

Mr Mountain said: "I think it's really bizarre that we started with a delivery date in Autumn then we're taught by Mr Tydeman in the update that was written to us that it might be spring next year. You must have had these discussions. I'm asking you a straightforward question [about dates] because islanders are asking, everyone is."

Scottish Conservative shadow transport minister Graham Simpson said: “Neil Gray’s admission that the Maritime and Coastguard Agency hasn’t yet signed off on the changes needed on the Glen Sannox should ring alarm bells.

“It seems incredible that after years of bungles and delays, this fiasco should still be dragging on.

“Any responsible government would be moving heaven and earth to sort out this scandal, get the vessels finished and at long last provide the lifeline service islanders deserve. Instead, we still have no assurance of when – or even if – this ferry will ever sail.”

A Scottish Government spokesman said: “Any further delay to the delivery of these lifeline vessels is extremely disappointing.

“We are continuing to engage with Ferguson Marine to fully understand the issues that have emerged and to explore all possible options to mitigate any additional hold ups.”