The company said it was part of its programme of cutbacks resulting in the downturn in the aerospace industry following the 11 September attacks last year.

It is hoped some workers can be retrained for other positions within the firm.

Figures released last month showed profits and sales at Shorts fell last year.

The new plane will result in up to 400 jobs

While profits at Northern Ireland's biggest company dipped only slightly at �55m in the year to January, sales were down by 10% at �450m.

During the last year, Shorts has cut its workforce by about 1,000.

Shorts' Canadian parent company Bombardier has relatively healthy order books.

In July, Bombardier announced it was building part of its new corporate jet at Shorts.

Decades

The plane, the Learjet 40, is designed to carry four passengers more than 1,800 miles.

Its fuselage is being built alongside that of the bigger Learjet 45 which is also constructed at the east Belfast factory.

Throughout the past year we have endeavoured to minimise the impact of the difficult market conditions on our permanent work force

Shorts spokesman

The new plane will result in up to 400 jobs in Belfast although that figure is not expected to be reached until the jet reaches full production.

The redundancy cut at Shorts has been one of the biggest single losses of jobs in Northern Ireland in decades.

At its height, the company had a workforce of 6,500.

Economy Minister Sir Reg Empey said he was deeply concerned about the job losses.

'Retraining'

Speaking in Washington, the East Belfast assembly member said he had discussed the situation with Michael Ryan, the company's vice president and general manager of operations.

Sir Reg said he had been aware since last September that there was potential for further jobs to be under threat.

Shorts said it had advised the trade unions and employees that "a further 461 jobs were surplus to requirements".

The downturn in the aircraft industry will end at some time, the last thing we need to do is reduce the skills base too far - that would be a disaster for the company

Walter Wilson Trade union committee

But the company said those going were "significantly less" than the number of workers jobs first thought to be at risk post 11 September because of efforts to keep losses to a minimum.

It was hoped to do so by repatriating work currently contracted out, redesignating and retraining workers for other jobs within the company.

A spokesman said: "The company very much regrets losing valued employees.

"Throughout the past year we have endeavoured to minimise the impact of the difficult market conditions on our permanent workforce.

"We will make every effort to assist surplus employees explore employment alternatives through our Interpoint outplacement centre which will be supported by government departments."

He said the company was continuing to invest in its Belfast operation.

"We are going through a difficult period, but by taking all steps necessary to protect our competitiveness we can be ready for the upturn in the market when it comes," he said.

Walter Wilson, secretary of the trade union committee representing all unions at the company, said: "It remains to be seen how many jobs we can save."

He said many of those facing redundancy were key skilled workers.

Mr Wilson said a 90-day discussion period meant no jobs would go before December.

"The downturn in the aircraft industry will end at some time, the last thing we need to do is reduce the skills base too far - that would be a disaster for the company".