First Minister Humza Yousaf has promised greater transparency over the delayed and over-budget building of two ferries on the Clyde.

He told MSPs that he would consider what could be published from a lawyer’s investigation into whether the Ferguson Marine shipyard was given preferential treatment when it won the contract for CalMac. The cost of the ferries has soared from £97m to £300m and they are years late in being delivered.

Barry Smith KC has been examining the procurement process following claims that the Port Glasgow yard was given sight of a technical document and access to ferry owner Caledonian Maritime Assets (CMAL) that was denied to other bidders.

Amid months of pressure from opposition politicians and Audit Scotland over unanswered questions, Mr Yousaf pledged more transparency when he faced the conveners of all Holyrood committees.

However, he cautioned that “there are some areas and issues in relation to Fergusons in particular that are commercially sensitive, that if we were to release completely unredacted … would put Fergusons at a competitive disadvantage.”

The first minister insisted the Scottish government took the issues raised “very, very seriously indeed” and “that is why there is an investigation under way”.

He said: “I am more than happy to look at what can be published.”

Labour MSP Richard Leonard, convener of the Scottish public audit committee, said members had been met with “ministerial non-co-operation, senior civil servants evading scrutiny”.

He added that he was frustrated by “government bodies omitting evidence or unable to find evidence which then turns up”.

Mr Yousaf said: “I am absolutely committed to being not just upfront and transparent but making sure parliament is notified as soon as we can on really important developments in relation to Fergusons.”

Economy Secretary Neil Gray last week committed the government to completing the second ferry, known as Hull 802, after admitting it would be cheaper to commission a new one. The Glen Sannox is due for r completion by the end of this year and Hull 802 the end of 2024.

The meeting took place as it emerged that four ferries being built in Turkey for Scottish west coast routes are on course to be finished on time and on budget.

All of the ships are due to be delivered to Scotland by 2025.

Milestones were reached on Wednesday with the keel-laying of the second of two Islay ferries and steel-cutting of the first of two for the Little Minch.

CMAL said island communities should have confidence the four ferries being built at the Cemre shipyard in Turkey would be delivered as planned.