Number 10 insisted Britain will get the “good deal” that would negate the need for the aircraft maker which employs 14,000 people in the UK to relocate.
But it failed to allay the fears of workers at the manufacturer who said the closure of UK factories would have a “devastating” effect.
It comes after the firm said it would “reconsider its investments in the UK, and its long-term footprint in the country” if Britain was forced to leave the single market and customs union in March 2019 without a transition agreement in place.
Katherine Bennett, Airbus’s senior vice-president in the UK, said ministers had been made well aware of the company’s views during “extensive and frank” discussions.
But speaking to journalists on Friday a spokesperson for the prime minister said she is sure the firm’s fears are misplaced.
She said: “We are confident that we are going to get a good deal, one that ensures that trade is as free and frictionless as possible, including for the aerospace sector.
“The PM set out in her Mansion House speech that we want to remain part of the European Aviation Safety Agency and both the UK and the EU agreed that a final deal should ensure that the current level of connectivity is continued.
“The UK is a vital contributor to the success of the European aerospace industry and it’s in no one’s interests to disrupt the sector’s cross-border supply chains.”
Asked why the prime minister was pushing ahead with her Brexit strategy even though it appeared to be putting jobs at risk, the spokesperson replied: “Because people voted for it.”
Airbus would be among those firms hit hardest if the UK fails to secure the frictionless trade it wants, as it is supported by a network of suppliers across the EU – aircraft fly between the UK and European sites several times a day to deliver parts.
Darren Reynolds, a Unite the Union convener for workers, said they had “grave concerns” about the future.
Speaking outside an Airbus factory in Broughton, he said: “We’re coming into Article 50 in March and have not got any assurances on how we are going to get parts in and out of the plant going forward.”
He explained that he was sure that if the UK could not easily supply the wing sets to the firm’s final assembly lines abroad, then Airbus would “find someone who will”.
Mr Reynolds said he had visited Downing Street twice this year to discuss the impact of Brexit with ministers but was not sure they understood the concerns.
He said: “This site here employs 6,500 people; it’s key to this area and the northwest to have the jobs that we do, and you tell them about the infrastructure of the supply chain and everything around what we do that comes out of the Broughton plant, however they’re not giving any answers.”
Airbus has warned that the firm, which employs its 14,000 workers at 25 sites across the country, does not “deal in idle threats”.
Chief operating officer Tom Williams said on Friday: “We’re becoming increasingly frustrated with the lack of clarity and obviously time is running out – we’re coming up to less than nine months to go.
“Now we have to come to the point where we have to make serious decisions. Quite often those decisions are long term in nature and without clarity it’s too dangerous for us to proceed.
“We’re talking about decisions in terms of safety stocks, buffer stocks of components, assuming that there will be chaos at the borders and that material won’t be moving freely.
“We are talking about ‘do we invest in further capacity?’.”
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