A ‘no-deal’ Brexit could cost Bombardier up to £30m, the company has warned.
The multi-million pound bill would stem from stockpiling parts to mitigate the impact of a no-deal scenario.
Michael Ryan, the head of the firm's Northern Ireland operation, said the Belfast plant - which employs around 4,000 people - operates a "just in time" supply policy to avoid the expense of stocking excess materials.
However, there are fears that the movement of goods could be disrupted by long queues at ports if the UK is unable to reach an agreement with the European Union over Brexit.
The company uses hundreds of components that cross between the UK and the rest of the EU on multiple occasions.
Asked about the implications of a no-deal Brexit, Mr Ryan said: "The only solution to not having some sort of a deal will be to stockpile parts.
"That will cost us about £25-30m to hold a number of months' worth of material to avoid stopping our lines.
"That's money that should be being put into new product development, R and D (research and development) to allow us to keep doing business in the future, instead of managing a consequence or an uncertainty or frankly a lack of agreement.
The factory makes wings for the Airbus A220, which was known as the C-Series until Airbus took a majority stake in the aircraft programme amid concerns about the model's feasibility.
Bombardier is in the middle of a five-year turn around plan to improve its finances.
Mr Ryan added: "What we do not have is another £25-30m to be sitting in a store somewhere, either managing an issue which has happened or because we weren't able to get clarity on what might happen."
The firm will begin arrangements to stockpile goods by the end of the year if there is continuing uncertainty around Brexit.