Bombardier is Northern Ireland's largest manufacturing employer

The company warned earlier this month that jobs could go after employees rejected a union-backed four-year pay deal - with a pay freeze in the first year in return for employment assurances.

In the past week, trade unions have been seeking a mandate for fresh talks to try to renegotiate a pay deal with the company.

While a slim majority of workers voted for more talks, two out of the three main unions failed to achieve the necessary majority.

GMB members produced a unanimous majority, but Transport and General Workers' Union voted against, and the largest union at Shorts, Amicus, also narowly voted against talks.

UNION VOTING For: 1,862 / Against: 1,789 GMB: Majority for talks T & G: Majority against Amicus: Majority against

The company has said it is still willing to have further dialogue, but time is running out.

On Wednesday, a union official described the vote as "madness," but accepted the democratic wishes of their members had to be abided by.

BBC Northern Ireland Business Editor James Kerr said: "What it tells us is that there is an awful lot of ill-feeling on the shop floor and that management have, to some degree, lost the trust of their workers.

"They appear to feel, that even if they agree to this deal, a lot of jobs will still go."

Last week, two east Belfast politicians said the threat of redundancies could be lifted if workers accepted the initial pay deal.

Redundancy programme

Sir Reg Empey and Jim Rodgers held talks with senior management of Shorts' parent company Bombardier, after news of the heavy cutbacks.

Last month Bombardier Aerospace secured a contract worth more than $2.2bn with US Airways for a mixture of its 50 and 75 seat regional jets.

It was thought the order would secure the position of the rest of the Shorts workforce, with more than 3,000 employed on the two aircraft.

However, in a staff bulletin several weeks ago, the company said the redundancy programme would now be accelerated.

It said the recent ballot result rejecting a negotiated contract renewal proposal was "very disappointing and prevented the company from improving its competitiveness in these very difficult market conditions".

Bombardier is Northern Ireland's largest manufacturing employer, involved in the design and production of aircraft structures and engine covers.