Prospect national secretary Gill Wood said: "The PAC report is correct to highlight the lack of trained staff with the specific skills, capabilities and experience.

"But it fails to mention that more than 800 skilled Sellafield employees were encouraged to take early severance in 2010, thereby exacerbating the challenges for the clean-up. If lessons are to be learned then that lack of effective long-term workforce planning cannot happen again.

"The workforce and unions at Sellafield are also committed to making the site safer, more productive and cost effective. That is why we recognise that an effective solution to reducing the plutonium stockpile cannot be produced overnight.

"Again it requires a long-term approach backed with secure commercial contracts, which is why we welcome moves to explore all available options, including the possible re-use of plutonium as fuel."

Wood said Prospect understands the need for closer scrutiny, but warns that it must not detract from the goal of reducing high hazard risks safely and efficiently.

"We recognise that the contract with Nuclear Management Partners needs to have a sharp focus on delivery and back the recommendation that progress be reviewed on a regular basis.

"Our members would also like to invite PAC chair Margaret Hodge to visit the site and see first-hand the challenges, the dedication of the staff and the opportunities for future work from a different perspective."