One of the CalMac ferries being built at Ferguson shipyard on the Clyde is facing more delays – and, not for the first time, they stem from the liquefied natural gas (LNG) propulsion system.

Glen Sannox and Glen Rosa are the first ever ferries built in the UK which will be capable of running on LNG.

But the delivery of MV Glen Sannox has now been put back by two months and is not due until 31 July.

A decade ago the decision to build the dual-fuel ships was seen as a step towards a greener ferry fleet.

But those green credentials have since been questioned – and some believe the ships would have been in service years ago if a more conventional design had been chosen.

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