Bombardier is Northern Ireland's largest manufacturing employer

Members of the Amicus union voted by a narrow majority on Wednesday to strike over the continuing row about pay and conditions.

The union said the ballot demonstrated the depth of frustration among its members. There had been a total breakdown of industrial relations at the firm, it said.

A spokesman for Bombardier Shorts described the vote as "regrettable". He said it sent a strong negative signal to its customers.

In August, talks between unions and management broke down after the union delegation walked out of pay negotiations.

The news fuelled fears that the company would press ahead with job cuts.

Job cuts fears

More than 1,000 jobs are under threat at the company after 60% of workers voted in May to reject a proposed four-year agreement over pay.

At that time, union leaders accused the company of undermining the talks through their "inflexible position".

The company has already announced 580 redundancies in response to what it called "very challenging market conditions".

Bombardier in Canada has already made it clear that it needs to reduce the workforce in Northern Ireland in order to improve competitiveness.

It said it was essential that the company was "in the best position possible to retain contracts with its customers who are demanding very competitive, long-term price commitments".

The aerospace industry has been badly affected in recent years by events including 11 September, the consequent fear of terrorism, the downturn in the global economy, competition from low-cost carriers and the recent Sars outbreak.

Many airlines are in financial difficulties and have cancelled some aircraft orders and put others on hold.