Scotland’s publicly-owned ferry company is suing the government after missing out on a contract.
CalMac Ferries Ltd has raised a legal action against Scottish ministers who own the business on behalf of taxpayers.
The unusual legal move was confirmed by islands secretary Paul Wheelhouse in a letter to opposition colleagues.
Labour and the Tories said it was an astonishing situation that the Scottish government faced action by its own company.
CalMac is challenging a decision by ministers to award the £450m Northern Isles Ferry contract to commercial rival Serco in September.
The legal action effectively suspends the contract being awarded to Serco.
It is understood Serco’s existing contract will be extended to ensure services continue between the mainland and Shetland and Orkney.
In a letter to MSPs, Mr Wheelhouse confirmed: “Earlier today I answered a Government initiated question informing the Scottish Parliament that CalMac Ferries Ltd have raised legal proceedings on the Scottish Ministers’ decision that CalMac’s tender to operate the Northern Isles ferry services was unsuccessful.”
Scottish Conservative Highlands and Islands MSP Jamie Halcro Johnston said: “It’s quite incredible that the SNP is being sued by one if its own quangos.
“It tells you everything you need to know about the mess the SNP government has made of ferry services that a publicly-owned company wants to take it to court, leading to more uncertainty and delay for travellers.”
He added: “When factored in with the completely unacceptable delays with the two new ferries being built, the delays on reducing fares to Orkney and Shetland and its refusal to meet its pledge on fair funding for inter-island ferries, this really is turning into a fiasco.”
Scottish Labour accused the Scottish government of presiding over a ferry “fiasco”.
The party’s transport spokesman Colin Smyth said: “This fiasco exposes the SNP’s mishandling of this lifeline ferry services contract.
“Their incompetence and opposition to public ownership has led to the extraordinary situation we now have of a Government being taken to court by its own company.
“Meanwhile, communities who rely on these services have no certainty on what is going to happen to their lifeline services.”
Orkney’s Scottish Liberal Democrat MSP Liam McArthur said: “The letting of this contract has already been delayed by more than 18 months.
“Continued uncertainty over the future of the service is the last thing communities in Orkney and Shetland need.
“Ministers must do everything possible to resolve this dispute as quickly as possible”.
CalMac runs 33 vessels to over 50 ports and harbours, across 200 miles of Scotland’s west coast.
CalMac Ferries Ltd (CFL) is a wholly-owned subsidiary of David MacBrayne Ltd, which is wholly owned by Scottish Ministers.
The organisation is already embroiled in problems with the Scottish government over delays to two new vessels for its Clyde and Hebridean services.