THE TRANSPORT minister has declined to commit to a timescale for the long-delayed launch of long-delayed ferries for service Scotland's islands.

In the wake of concerns over the stalling over an over £60m budget for nationalised Ferguson Marine to enable the completion of the two crucial vessels next year, Jenny Gilruth was asked if one of the two ferries, only known as Hull 802 would be operational by early 2024 in the latest reschedule.

Ms Gilruth said: "Ministerial responsibility for Ferguson sits in a separate portfolio but we remain absolutely committed to the completion of those vessels and supporting our island communities that rely on that type of vessel."

There are fears over whether Glen Sannox and Hull 802 will ever set sail as an agreement over the publicly funded budget has stalled since September.

Ministers approved £15m of an £87m extra public funding request in December to deliver the ferries as a "precautionary response to a material risk related to cash flow", while they consider whether the increased costs were value for money.

READ MORE: Fears new ferries may never sail as Ferguson Marine budget stalls

And a row has erupted over an apparent £11m shortfall in the extra money that executives indicated was needed in September to deliver the ferries.

The stalling over the budget led to concerns that it is a major factor in the nationalised firm facing the prospect of being closed while being sanctioned after failing to lodge its annual accounts on time.

HeraldScotland: Nicola Sturgeon with Ferguson Marine owner Jim McColl

Glen Sannox and Hull 802 which were due online in the first half of 2018 when Ferguson Marine was under the control of tycoon Jim McColl, with one initially to serve Arran and the other to serve the Skye triangle routes to North Uist and Harris, but they are at least five years late. The last estimates suggested the costs of delivery has more than quadrupled compared to the original £97m cost.

Scottish Conservative shadow transport minister Graham Simpson quizzed the minister over whether there was a shortfall in the budget, and whether it would impact on the ferries' delivery.

Ms Gilruth responded: "Scottish Government officials, of course are working closely with Ferguson's to review assumptions behind any revised costs and a schedule on how spend aligns to the vessels' delivery.

READ MORE: Ferguson Marine did not bid for new ferries contract given to Turkey

Highlands and Islands MSP Edward Mountain, the former convenor of the rural economy and connectivity committee whose probe into the construction of the ferries for CalMac branded the management process a "catastrophic failure" sought assurances over action being taken after ferry operator CalMac warned the next two years will be "challenging" for residents of Scotland's islands due to the age of its fleet.

Chief executive Robbie Drummond also apologised to residents of Arran for recent disruption to services.

He said shortage of spare vessels was also driving disruption.

Ms Gilruth said in the short term the Scottish Government was investing "resilience funding of at least £4m per year to maintain the existing fleet.

"We continue the search for additional tonnage that can be chartered in the short term," she said."

Video: Glen Sannox assisted to Ferguson Marine last year

Mr Mountain asked for an assurance that a spare ferry will either be rented or purchased to cover the next two years.

Ms Gilruth said: "I'm more than happy to give Mr Mountain confirmation in relation to that request. I think it's important to reiterate that when I appeared in front of Mr Mountain's committee only last week, I gave a very clear guarantee in relation to the search for ongoing additional capacity on the network.

"We will absolutely continue to look for the spare vessel that Mr Mountain has alluded to. I recognise very much that there's a challenge in relation to the current fleet and the availability of services at the current time.

READ MORE: Ferguson Marine: Ferry firm sanctioned twice over financial fails

"He has an assurance from me that we are absolutely seeking the additional tonnage that we so readily need in relation to the CalMac fleet."

Some 18 of of CalMac's 35 working ferries deployed across Scotland are now over 25 years old - said by many experts to be the lifespan of such vessels.

The oldest in the CalMac fleet is is the Isle of Cumbrae which is 47-years old.