Offshore trade unions have teamed up to form a co-ordinated "fightback" against cuts and changes affecting workers in the troubled oil and gas sector.

The North Sea has been hit hard by plummeting oil prices, with industry body Oil and Gas UK estimating 65,000 jobs have been lost since 2014.

The newly-formed Offshore Co-ordinating Group (OCG), with representatives from Unite, the RMT, GMB, Balpa and Nautilus, says it believes that number is now significantly higher.

It said workers continue to experience attacks on their terms and conditions and there are growing fears over the impact of new working practices on health and safety.

This includes the increasing use of the three weeks on, three weeks off shift pattern which see employees working 12-hour shifts for 21 days in a row.

The OCG said: "Experienced trade union representatives in the sector report that workforce moral has never been lower.

"The impact on the north east and Scottish economies has also been severe and the offshore unions are far from satisfied that the nature and scale of recent government announcements is sufficient to meet the numerous challenges facing the region and industry.

"Despite the crisis currently affecting our members in the North Sea, the offshore unions are convinced there is a future worth fighting for.

"But building a sustainable future demands that the industry's response to current challenges must be based on collaboration, innovation and common high standards and a mature assessment of why costs in the UKCS (UK Continental Shelf) continue to be higher than similar jurisdictions."

In the first of its state of the industry reports, the OCG said oil and gas companies should stop demanding cuts from contractors, which it says have a direct impact on jobs and safety, and workers who have been made redundant or are at imminent risk of redundancy must be supported to find skilled employment at similar rates of pay.

The new body will publish research looking at working hours across a range of safety critical occupations in the spring.