A simmering row over the ability of the UK’s industrial base to underpin its world-leading offshore wind programme erupted again as “furious” unions in Scotland said a deal to build turbine foundations at a local fabrication yard has collapsed amid “political failure”.

Hopes that local facility BiFab would make eight jacket foundations for the EDF-led 448MW Neart Na Gaoithe (NNG) project faded when the yard’s owner said its ability to deliver the work had been hobbled by lack of guarantees from the Scottish government.