A SMALL band of protesters heckled Prime Minister Boris Johnson as he visited an engineering firm in the shadow of the Transporter Bridge yesterday.

But his two Battle buses largely obscured the objectors, who shouted from behind tall metal railings, as he stood on a raised platform and spoke to dozens of Wilton Engineering employees during a question-and-answer session.

Standing shoulders above a sea of hard hats, he first of all seemed to inadvertently reveal a manifesto pledge to raise the National Insurance threshold from £8,628 to £12,000 a year, after being asked about whether low tax ‘was for the likes of him or the likes of us’.

At the firm, in Port Clarence, just over the Tees from Middlesbrough, he also spoke about making the economy strong and supporting low tax for working people.

On his briefing notes, just visible under his arm, “Get Brexit Done’ seemed to be the main point he was tasked by his advisors to get across.

And he asked workers: “How enthusiastic are you for two referendums next year?” as he claimed that would be the case under rival parties. The Conservatives, he said, were ready for Brexit.

“(The deal) needs no further negotiation,” he said. “It just needs baking in the oven, gas mark 8, and it will be done. It will be pretty crispy by the end of January, but it will be done.”

He reiterated promises – everything from the 20,000 extra police officers to plans for record spending in the NHS, which he described as ‘beautiful’ – and in response to a question about selling off the NHS, said: "It is a complete invention. Under no circumstances will the NHS be on the table in any trade negotiations whatsoever."

He promised £34bn spending on the NHS, to upgrade 20 hospitals and build 40 new ones.

"We will invest in the long term and we can, because we understand what is takes to have a strong economy," he said.

The only question he appeared to flounder on was when he was asked if a report by the Intelligence Security Committee into the potential for Russian interference in UK democracy, would be published before the December 12 election, and why it was being withheld.

"I saw no reason whatsoever to change the time table for that report just because there is a general election on," he said.

"I've seen no evidence of Russian interference in any British democratic event."

Mr Johnson also reiterated his commitment to nuclear defence after a worker asked him about BAE contracts.

As he stood on the very part of the river which in its glory days was once a cornerstone of the shipbuilding industry, he said: "My dream is to have a shipbuilding renaissance in this country. I see a big future (for it) in this country."

He toured the 54-acre Wilton Engineering site, which builds large structures for the offshore oil and gas, marine, and wind turbine industries, and also carries out decommissioning work.

Far from being overwhelmingly supportive of Brexit, one engineer said before the session that he backed a People's Vote – and said there were many there who were also supportive of the idea.

But another worker asked about immigration and European workers taking jobs from British people. Mr Johnson renewed his pledge for an Australian points-style immigration process which he said would allow skilled workers access to Britain.