Up to 270 manufacturing workers are to lose their jobs at one of Bradford's leading hi-tech firms, it was announced today.

Filtronic Comtek, the Saltaire firm which makes components for all the world's leading mobile telephone companies, is to lay-off more than half of the workforce at its site in Salts Mill Road.

Today the firm said it was "deeply saddened" to be announcing the move but said it could no longer sustain large-scale manufacturing at the site.

The work will move predominantly to China, where Filtronic already employs more than 1,000 people and is expanding rapidly.

Last August, Filtronic chairman Professor David Rhodes told the Telegraph & Argus that it was "inevitable" that more work would move overseas, in a large part due to the impact of the strong pound.

More than 80 people were made redundant in September, leaving around 500 staff remaining in Saltaire.

Today's announcement will effectively see half of that number leave. A 90-day consultation process is now under way.

It will leave only a small manufacturing operation at a site which once employed more than 800 people. The head office will remain in Saltaire as the centre of the company's design and engineering expertise.

A spokesman for the firm said today: "Unfortunately, it is not possible for us to remain competitive while manufacturing in the UK. There will still be some manufacturing in Saltaire, but it will be very much on a reduced scale.

"It is a very sad day. There will be a lot of people affected here and it really is not their fault. Unfortunately, it is one of those decisions that sometimes you find yourself having to make."

He said that staff had been aware for some time of the problems facing the company, which is one of Bradford's best-known and listed on the London Stock Exchange.

"They will have recognised that there has been a lot less activity on the site, but people are always shocked when they hear this sort of news," he said. "However, operations in the UK are just not competitive in the world market."

Filtronic Components, the Baildon-based part of the company which specialises in making components for the defence sector, is not affected by today's announcement.

The company said that part of the business would continue to grow in the UK along with its advanced compound semi-conductor plant at Newton Aycliffe in County Durham.

At the time of Filtronic's last results announcement in August, Prof Rhodes admitted that the Saltaire manufacturing plant had an uncertain future.

He said: "Unfortunately, I can't do anything about what the Government is doing in terms of making the pound strong.

"At the end of the day, the compound semi-conductors and defence business will remain in the UK. But when it comes to other things that we can move around the world, there's not many people who can afford to do it here."

Today's announcement is the latest in a series of job blows for the Bradford manufacturing sector over recent years.

The heaviest job losses last year came at the piston plant of struggling car components manufacturer Federal Mogul, where 380 people were made redundant.

Last month, the T&A revealed that 85 people were to lose their jobs at Switchgear & Instrumentation in Ripley Road, Bradford.