BORIS Johnson’s idea of a road link between Britain and France could be “a bridge too far” for any British company, according to the Eurosceptic boss of a Dorset steel firm.

Reidsteel welcomed Mr Johnson to Christchurch during the 2016 referendum campaign and managing director Simon Boyd chaired Leave lobby group Business for Britain.

But Mr Boyd was sceptical that he would live to see the building of a 22-mile road bridge between Britain and France, as the foreign secretary proposed during a summit with French president Emmanuel Macron.

Reidsteel has built a number of heavy road bridges, but Mr Boyd said: “It would be too big for us. It would be a bridge too far.

“I think it would be for any UK company. When they built the second Severn Crossing to Wales, these big infrastructure builds take a consortium.”

He said such a bridge would probably be built by a consortium involving both a French and British company.

“It’s such a vast project. There’s nothing wrong with ideas but it would take serious financial commitment,” he said.

It would be a challenge to carry out the construction in the biggest shipping lane in the world, he added.

“If people didn’t have great ideas, nothing great would ever be done,” he said.

“I doubt we will see something like this happen in my lifetime.

“It’s not un-buildable but I just don’t see it happening any time soon. We’ve got to get more focus on manufacturing and industry.”

Downing Street seemed to pour cold water on Mr Johnson’s proposal soon after he made it, telling journalists there were “no specific plans” for such a bridge.

A panel of experts would look at major projects together, a spokesman for the prime minister said.

The UK Chamber of Shipping has also raised doubts about the feasibility of the building project, pointing out that the largest ships in the Channel stand 70 metres above water.

A 34-mile bridge has been built between Hong Kong and Macau at a cost of £12billion but has not yet opened to traffic.

Other commentators have said that to allow for passenger ships 70 metres tall, the pylons supporting a Channel bridge would need pylons more than 500m tall, much higher than anything built so far. The large number of pylons required could interfere with free passage of shipping.