A new order for Bombardier C Series 300 jets by British Airways owners IAG is expected to be announced soon, according to reports.
The deal is said to include a number of the jets for British Airways and low-cost airline Vueling, as well as up to 10 for Aer Lingus.
Both Aer Lingus and British Airways fly from Belfast City Airport.
The Canadian aerospace giant, which employs 4,500 people in Northern Ireland, makes the wings of the C Series passenger jet in its Belfast plant.
Aviation industry sources were discussing the new order at the weekend on social media.
However, a spokesman for IAG said it could not comment on the order claim.
And a spokeswoman for Bombardier in Northern Ireland said: "We don't comment on speculation, nor on any potential discussions we may or may not be having with specific customers.
"Bombardier will, however, announce any material agreements with a customer if and when they are finalised."
Back in June last year IAG boss Willie Walsh told the Belfast Telegraph that the Bombardier CS300 jet was "definitely one we are prepared to look at".
On the back of other orders for the C Series 300, including deals with Delta Airlines and Lufthansa subsidiary Swiss, Mr Walsh said people were starting to look more closely at the jet.
Mr Walsh added: "The fact they have had the significant orders (is encouraging), the Delta order on the back of the Lufthansa one.
"I think everyone looking at the aircraft wanted to see a commitment from major operators to it. You don't want to be the only person operating the aircraft.
"A critical issue for airlines with an aircraft like that, is you want to make sure you have technical support in all of the airports, or as many of the airports (as possible)."
Speaking about the growing success of Bombardier's C Series, Mr Walsh said: "I think it's a big achievement for them, as Delta and Air Canada are two very significant (airlines).
"It puts that aircraft into play now, and I suspect that you will see a lot more airlines (looking at it).
"The critical issue with them, as it always was, is how competitive can you be on price."
"They had to get a scale of order to make them relevant for the industry."
Just last week the Canadian government announced it would lend Bombardier $372.5m (£225m) to help it secure more orders for the C Series jet, and for research and development activities for its Global 7000 products. Some components for the Global 7000 are made in Belfast.
Bombardier has already received $1bn in funding from the regional government in Quebec, where the company is based.
And the C Series programme also benefited from $350m in loans from the Canadian government when it was launched in 2005.
Bombardier last year announced job cuts of 1,080 over two years in its Northern Ireland operations due to difficult market conditions and what had been weak sales of the C Series - which is trying to break into a market dominated by Boeing and Airbus.
The 2015 launch of the C Series had been delayed by over two years and was around $2bn over budget. Orders were also lower than expected, but morale was boosted last April when Delta Airlines placed an order for 125.