The UK Chamber of Shipping has warned opponents of the UK's EU withdrawal agreement it is now time to "put up or shut up".

CEO Bob Sanguinetti said those who dislike the terms of prime minister Theresa May's deal must either accept it or demonstrate an immediate unambiguous and workable alternative.

He said: “International agreements rarely please everyone, and I accept this deal gives neither Leave nor Remain campaigners everything that they want, but we have now run out of time.

“This deal has been struck after years of complex, detailed and technical negotiations. We respect those who cannot support the proposed deal, but their dissent requires them to put forward a clear, unambiguous and workable alternative immediately. In short it’s time to put up or shut up.”

The Chamber is also arguing that a no-deal is too big a risk to take.

“I know people are tired of business groups warning of a no-deal scenario," the CEO said. There is however a direct relationship between political decisions and people’s day-to-day lives and it is our duty to alert them to the facts.

“It may be the case that over the medium term markets will shift and adapt well to a no-deal economy, but nobody truly understands the damage that will be done in the meantime.

No-deal a disaster

“In a no-deal scenario, it is a fact that there will be long delays in ports putting manufacturing supply chains and just-in-time deliveries of pharmaceuticals and fresh food at risk. It is a fact that costs would go up for consumers," he added.

"It is a fact that this will damage both the UK and the EU. The question is how long it would take to sort all that out – and for that there is no clear answer."

Sanguinetti argued that there was still work for government and the EU to do.

He said withdrawal is just one part of the process.

"If the UK Parliament does agree to this deal, it should do so with its eyes wide open – even the strongest supporters of it need to realise the ramifications are profound," he said.

"If the UK were to fall on to the backstop arrangement in two years' time then the UK would continue to have no say in its rules and regulations on a whole range of matters.

"We would be trusting the EU to negotiate a future relationship in good faith. The government and the EU need to prove that such trust is warranted.”