Two SNP MSPs have distanced themselves from their own parliamentary committee’s report criticising Nicola Sturgeon over her involvement in the Ferguson Marine ferries fiasco.

Colin Beattie and Willie Coffey said they do not agree with a number of conclusions in the 124-page report on the troubled programme to build MV Glen Sannox and the unnamed Hull 802 on the Clyde.

The report rebukes the departing First Minister for inadequate record-keeping, ignoring Transport Scotland’s advice in 2015 and sidelining the Transport Minister to make the announcement of the preferred bidder herself.

Neither ferry has been completed and total costs have tripled to more than £300 million. It emerged last week that the final price tag remains unknown.

Richard Leonard, the committee’s convener, said there had been significant failings throughout the process. “The people of Scotland have been badly let down by this project,” he said.

“There have been collective failures at government and agency level from the start. It has been dogged by a lack of transparency, by ineffective governance arrangements, by poor record keeping within the government and by baffling communication failures.”

But the SNP members on the committee challenged the report’s findings and claimed it was rushed out by opposition politicians to coincide with Ms Sturgeon’s final First Minister’s Questions today in the Scottish parliament.

A spokesperson for the SNP group said: “In nationalising the yard in 2017, Nicola Sturgeon and the SNP Scottish Government saved hundreds of Scottish jobs, created many more, and delivered a lifeline for the future of shipbuilding on the Clyde.

“The headlines chased by the committee convener significantly embellish the actual substance of the report, which offers very little in the way of new information.

“Despite six months of work [and more than 16 hours of evidence] through this inquiry, the Committee has largely failed in its core purpose – to determine how public money was spent and whether that represents value for money.

“Instead, opposition politicians chose to rush through the report before the First Minister stood down and pursued a narrow political agenda at the expense of workers at the yard who are committed to delivering these vessels.”

The committee is also critical of outgoing Deputy First Minister John Swinney, as well as Humza Yousaf and Keith Brown, who both served as transport ministers, and Derek Mackay, who was finance secretary until 2020.

It says Mr Brown’s lack of co-operation obstructed their scrutiny of the deal and says three requests for information had to be made before he gave an answer that cast doubt on previous evidence.

It questioned whether Ms Sturgeon should have personally attended Ferguson to announce it as the preferred bidder for the contract, saying the move “almost certainly” weakened the negotiating position of the ferry-owning body Caledonian Maritime Assets Ltd (CMAL) when problems emerged later.

There was concern about “weak” record keeping when ministers intervened at various stages of the process.

The report highlights a 2017 meeting between Ms Sturgeon and Jim McColl, the chief executive of Clyde Blowers, which rescued the yard from insolvency in 2014. It says there did not appear to be a full record of what was discussed.

The committee suggests reform of government agencies such as Transport Scotland and CMAL.

The former management of Ferguson is not spared criticism. The committee concluded that decisions taken in the yard contributed to the “serious problems” in the building process.

The committee recommends that a further inquiry was needed once the vessels were completed.

Mr Leonard said lessons needed to be learned.

“That means much needed reform of governance arrangements for future vessel projects,” he said. “But it also means a change in the way the government and its agencies conduct themselves and are accountable to parliament and the people. That is a challenge for the permanent secretary and the new first minister.”

Scottish Conservative shadow transport minister Graham Simpson said: “A scathing committee verdict on the SNP’s long-running ferries fiasco was inevitable, but this bombshell report shows up a series of failures on an unprecedented scale.

“It beggars belief that, even after this exhaustive attempt to get to the bottom of this murky business, we still do not know who made the final decision to sign off on this deal.

“But it is clear that a lack of transparency and a rush to make announcements for political purposes compromised the integrity of the procurement process. And that SNP members were still trying to conceal information right up until publication.

“This sorry business is one of the most disastrous and shameful legacies of Nicola Sturgeon’s period as First Minister.

“She should take the publication of this damning report as a final opportunity to apologise to the Scottish taxpayer for the reckless waste and secrecy that has surrounded this fiasco, and most importantly to islanders, who have been betrayed at every turn by her SNP Government, and deprived of a lifeline service.”

CMAL said that it had “acted professionally and appropriately” in line with its legal obligations. Its spokesman added: “We provided impartial advice and voiced our concerns when necessary. Like everybody involved, we are extremely disappointed by the delay to the two vessels, which island communities are desperately in need of.”

David Tydeman, the chief executive of Ferguson since February last year, said that the focus of his team was on completing the two ferries and securing a future for the yard.

The report follows those published by Audit Scotland, the public spending watchdog, and Holyrood’s rural economy and connectivity committee.