Manufacturers from across Europe have issued a warning that failure to achieve a deal on the UK's departure from the European Union will be "highly damaging" for industry in both Britain and the rest of the continent.
The warning, on the day that Prime Minister Theresa May triggers withdrawal talks under Article 50, came from the Ceemet group of organisations representing more than 200,000 manufacturers.
Britain's EEF - which forms part of the group - said failure to reach a deal would risk the "lifeblood" of Britain's economic success.
Meanwhile, the UK's digital industry trade body said it was vital for tech companies to avoid a "chaotic" Brexit which sees the UK crash out of the EU on World Trade Organisation terms.
And the TUC urged Mrs May - who has insisted an exit agreement and trade deal can be completed within 18 months - to take her time over negotiations in order to ensure that British workers' rights keep pace with the remaining 27 EU states.
Speculation over a "hard Brexit" on WTO terms has mounted since Mrs May declared that "no deal is better than a bad deal".
Foreign Secretary Boris Johnson said exit without a deal would be "perfectly OK", and Brexit Secretary David Davis said on Monday that Whitehall had done a great deal of planning for that outcome.
But Ceemet director-general Uwe Combuechen called on Britain and the EU to deliver "a stable and orderly exit, preserving as much as possible the often complex and delicate trading relationships that are in place".
Calling for "pragmatism on all sides", Mr Combuechen said: "If we are to avoid a 'lose-lose' outcome for European manufacturing, it is essential that all parties work towards a reasonable deal for industry, while ensuring the integrity of the single market.
Simply put, a negotiation which produces no deal would be highly damaging for industry in the EU as well as the UK."
EEF chief executive Terry Scuoler said: "It is imperative that the Government is focused on securing a deal that will enable both British and European businesses to flourish, investment and innovation to continue and trade to flow.
This will be the lifeblood that is key to the UK's future economic success - we cannot afford to see it disrupted or turned off in mid flow.
"Forget all notion of crashing out of the EU without a deal and leaving business to pick up the pieces - focus instead on an orderly and smooth transition, the continuation of barrier-free trade, minimisation of costs and ongoing access to required talent and skills.
"Nothing less will do."
TechUK chief executive Julian David said that a smooth conclusion to the negotiations was "vital" for the UK's digital sector, which employs three million and accounts for 24% of Britain's exports.
"A chaotic Brexit that results in the UK falling back on WTO rules will benefit no one," he warned.
"The tech industry wants to see a trade agreement that ensure the industry continues to grow, including continued market access, frictionless movement of talent and a robust legal process for cross-border data flows.
A new relationship must be forged that not only works for today's economy, but for tomorrow's digitally enabled world."
TUC general secretary Frances O'Grady said Mrs May needed to "take the time to get the best deal for Britain - not just the fastest deal".
Ms O'Grady said: "The best deal will guarantee that hard-working Brits keep their hard-won rights at work - and that in the years to come they won't miss out on protections that Dutch, Spanish and German workers get.
"The best deal has to protect good jobs, with decent wages, by keeping our trade free from tariffs and unnecessary bureaucracy.
"And it has to end the disgraceful uncertainty for workers from other EU nations who've made the UK their home."
Adam Marshall, director general of the British Chambers of Commerce, said businesses want to see "a pragmatic and grown-up dialogue on the real-world issues, rather than verbal volleys between London and Brussels".
"In the early weeks of the negotiation process, businesses would like to see an effort to secure simultaneous exit and trade talks," he said.
"Concluding exit and trade negotiations at the same time would moderate adjustment costs for UK businesses, and enable trade between UK and EU firms to continue with less disruption."
A Government spokesman said: "The Prime Minister has been absolutely clear that we will pursue a bold and ambitious free trade agreement with the European Union as a priority, allowing for the freest possible movement of goods between Britain and the EU.
"The agreement we are seeking should give British companies the maximum freedom to trade with and operate within European markets and allow European businesses to do the same in Britain, that is in the interests of both the UK and the EU.
"Our position on EU nationals is crystal clear.
"We will seek the earliest possible agreement to secure the status of EU nationals living in the UK and that of UK nationals living in the EU."