LONDON (Reuters) - Britain’s Chancellor of the Exchequer Philip Hammond said it would be against British people’s interests to leave the European Union without an exit deal, but declined to say how the government would respond if parliament refused to back its Brexit plans.

FILE PHOTO: Britain's Chancellor of the Exchequer Philip Hammond leaves 11 Downing Steet in London, Britain, December 17, 2018. REUTERS/Toby Melville/File Photo

With less than three months before Britain is due to leave the EU, Britain’s parliament on Wednesday began a five-day debate over Minister Theresa May’s deal with the rest of the bloc ahead of a vote in the lower house next Tuesday.

May has refused to retreat from her unpopular deal, which envisages close trading ties with the EU after leaving in March, pressing ahead with a vote she is expected to lose.

“I firmly believe that my job is to look after the welfare and interests of the British people and I conclude that it would not be in their interests to leave without a deal,” Hammond told an annual reception hosted by European planemaker Airbus.

British lawmakers earlier on Wednesday demanded the government come up with a plan B within days if she loses the vote on her deal to leave the European Union.

Asked how in that situation the government would prevent a ‘no-deal’ Brexit, Hammond told Reuters: “We are very determined that we need a deal. We need a deal that allows us to continue to co-operate and to have a smooth and orderly exit and we’ll make sure that we do.”

May’s allies have said there is no ‘plan B’ that would break the parliamentary deadlock.

Hammond was speaking after Airbus AIR.PA Chief Executive Tom Enders stepped up pressure on decision-makers to end months of uncertainty over the terms for Britain's departure.

The company, which employs 14,000 people in Britain and builds most of its commercial airplane wings there, has spent tens of millions of euros on contingency plans including extra stockpiling of parts in anticipation of border delays.

“What we and many other British businesses need most urgently, is for politicians from all sides to come together and pass a pragmatic agreement that allows an orderly Brexit,” Enders said, with Hammond and other politicians in the audience.

“We don’t see any specific benefits in the current deal. It’s just a lot less bad than a ‘no deal’,” he added.

A so-called ‘hard Brexit’ with no deal could have consequences for future Airbus investment in Britain, Enders said, reiterating previous warnings.

Responding to Enders’ comments in a speech, Hammond said the government’s job was to ensure “that it will be business logic that keeps you here in the years ahead.”

Airbus is planning for a no-deal Brexit as its “baseline” scenario, according to a November staff memo.