THE transport minister has admitted he does not know when Ferguson's will finish the £97m ferries at the heart of a legal battle between the Port yard and the government.

Michael Matheson says the two new CalMac vessels may not be ready for use on their island routes until 2020 - but has warned it could be even later before they are delivered.

He made the remarks as he appeared before a committee of MSPs at Holyrood.

One of the vessels, Glen Sannox, was launched in November 2017 by First Minister Nicola Sturgeon but is still at the quayside while work on the other ship, Hull 802, is also far from complete after the high-profile contract ran into trouble and became mired in controversy.

Ferguson Marine say design changes and technical challenges have caused problems and they expect to lose £40m on the contract.

Greenock-born MSP Jamie Greene, who sits on the rural economy and connectivity committee, challenged Mr Matheson over the saga.

He asked the cabinet secretary: "Can you give people living on our island communities any indication as to when they might expect these new ferries in operation?"

Mr Matheson told the committee that there was uncertainty about whether the dual-fuel ships could be sailing next year.

He said: "Where we are with these two vessels is simply not where any of us would want to be.

"We want to see these vessels being utilised and on routes.

"At the present moment the indications are they expect both vessels to be completed next year, one in the earlier part of the year prior to the summer, and one later in the year.

"However, there are still some questions about their ability to keep to those timescales."

The ferry work was awarded to Ferguson Marine as a fixed-price contract but the yard subsequently sought additional funding, citing 'unforeseen complexities'.

The yard has started legal action against publicly-owned Caledonian Maritime Assets Ltd claiming that design changes have caused cost increases, while CMAL deny there have been any significant design alterations.