Bombardier is Northern Ireland's largest manufacturing employer

Up to 1,700 jobs in Northern Ireland depend on the C-series, a plane with more than 100 seats, going ahead.

The company has agreed a �180m aid package with the government, but no engine maker is on board.

At the Paris airshow on Monday the aviation industry heard what progress had been made.

The wings and engine-pods would be built in Belfast.

The firm confirmed it is in detailed discussions with an engine manufacturer, which until now, had been a major stumbling block.

Michael Ryan, vice president of Bombardier in Belfast, said the company had been "working really sincerely with many partners" to form an agreement which would allow the formal launch of the aircraft.

"The engine situation was outstanding and hopefully we are at the stage now where we have another milestone with getting Pratt and Whitney on the programme," he said.

"We have not signed them up yet to a contract, but certainly their involvement with us, from a technical and commercial point of view now, is going to increase and we would hope we will get to a situation where we would have them on board."

Mr Ryan said the company had always kept the workforce abreast of developments.

Cautioned

"We have made clear that all of our programmes eventually have a maturity and a life in aerospace terms and some of our programmes are reaching that stage.

"Therefore, as you know, we have been reducing our manpower over the past couple of years," he said.

"We have cautioned and been very open with our workforce that the volume of jobs associated with this programme are a number of years away and we still have some challenges in the short term with where we sit with some of our current programmes."

BBC NI business editor James Kerr said Bombardier has been considering a new larger family of aircraft on and off for several years, but that the engine issue was a "major stumbling block".

"Some sceptical industry analysts will be looking for reassurance that the aircraft will get the go ahead," he said.