A project to replace the ageing search and rescue helicopter fleet based on Anglesey has been suspended.
The £7bn project was one of several which have been put on hold or cancelled as part of the UK government review of spending.
Albert Owen, the Labour MP for Anglesey, said decisions like this "hit industry and the young people of the island hard."
The Ministry of Defence said it hoped the review would be "rapid".
In February, the then Labour government said the service currently provided by the RAF, Royal Navy and the Maritime and Coastguard Agency would be run by the private consortium Soteria.
The 24-hour service would be run from 12 bases around the UK from 2012 under the plans.
Soteria said they would also provide new aircraft - believed to be the Sikorsky S92 helicopter - to replace the ageing military Sea King helicopters over a three-year period.
The new fleet would travel 30% faster and have the capability to attend low-level overland night-time incidents.
They would also have forward-looking infra-red equipment and be fitted with fully integrated de-icing equipment for much improved performance in severe winter conditions, Soteria said.
But on Thursday Danny Alexander, chief secretary to the Treasury, announced the plans would be immediately suspended.
An MOD spokesperson said the plan had been to deliver a "a harmonised Search and Rescue Helicopter Service for the United Kingdom for some 25 years from 2012".
"Given the pressures on public spending, the MOD and DfT [Department for Transport] intend to conduct a rapid, but thorough, review of this project."
Prince William, who is known as Flt Lt Wales, is learning to fly Sea King helicopters at RAF Valley on Anglesey.