Bombardier Aerospace in Belfast has announced a further 1,050 jobs are to go following the rejection by workers of a four-year pay proposal that had been recommended by both the company and the trade unions.

The job losses are to come on top of 1,180 redundancies which were announced in March, according to a spokesman. Of this number, 550 have already been laid off, bringing the numbers employed at the aircraft manufacturer to 5,700.

Following yesterday's announcement, it is expected that the number employed will drop to 4,070 by next year. Further job cuts are envisaged, the company said yesterday. Two years ago Bombardier, formerly Shorts, employed 7,600 workers.

A spokesman for one of the unions involved said he believed that the 1,050 redundancies announced yesterday could rise to 2,000 in the longer term as further contracts came to an end or were dropped.

Mr Andy McGivern of the GMB union described last week's vote by the workers as a "disaster" but said any initiative for a re-run of the vote would have to come from the workforce. The pay proposal was rejected by 60 per cent of the unionised workers.

A spokesman for the company said it was not winding down operations in Belfast, but rather seeking to protect core profitable operations. He said a four-year pay deal, involving a pay freeze in the first year, was required to allow the company address costs and remain competitive.

In a statement to employees yesterday, the company said competitiveness needed to be improved in what were very difficult market conditions. The rejection by workers of the recent pay proposal prevented the company from improving competitiveness, the company said. As a result, it was going to withdraw from a number of under-performing contracts, with the resulting loss of 1,050 jobs in Belfast.

A review of manpower levels in the light of the new layoffs will take place, possibly leading to further jobs cuts. All capital investments have been stopped, with the exception of health, safety and environmental issues. The breakdown of any major equipment that could not be economically repaired, would lead to the off-loading of the work associated with that process, the company said.

The apprentice intake for 2003 has been cancelled, the company said, and bids for two contracts, or packages, have been withdrawn "because we cannot guarantee our costs".

"Either of these packages would have greatly reduced the market-driven redundancies that we will face later this year and next year," the company said. It said it would not be seeking new contracts which would require investment by the company. "The absence of any new work will mean that as current programmes run out, more job losses and closure of facilities will occur.

"We deeply regret that we are forced to make these decisions but we must take action now to reduce costs in order to hold on to our remaining contracts and protect our business and the remaining jobs in the longer term."

The unions will require a fresh mandate from the workforce before they can re-open negotiations with the company.