Labour leader Jeremy Corbyn made a bold claim about Brexit when he launched his party's election bus in Manchester on Tuesday 9 May. "That issue has been settled," the left-winger told his supporter in the north-west of England.

Putting aside calls for a second EU referendum and the fact that last June's vote was very close (52% Leave, 48% Remain), what exactly is Labour's Brexit policy?

"Labour wants a jobs-first Brexit," Corbyn said. "A Brexit that safeguards the future of Britain's vital industries, a Brexit that paves the way to a genuinely fairer society, protecting human rights, and an upgraded economy."

In other words, Labour wants a so called "soft Brexit", that is opposed to a "hard Brexit" which would see the UK trading with the EU on default and less favourable and World Trade Organisation (WTO) rules.

Corbyn and his Shadow Brexit Secretary Sir Keir Starmer have phrased the positioning another way – they want "tariff-free access" to the economic bloc.

The problem for Labour is that securing full, tariff-free access to the EU's single-market would require Britain signing up to free movement of people rules. And immigration, of course, was a major issue during the EU referendum campaign, with the official Vote Leave group backing an Australian-style visa points system.

Starmer, at a 25 April press conference in London, admitted that free movement would "have to end" when the UK no longer maintains its full access to the EU single-market after Brexit.

"As it currently stands, membership of the single market is incompatible with our clarity about the fact that freedom of movement rules have to change," he said.

But Starmer confused matters thanks to an interview he conducted with the BBC. "People from Europe could carry on coming here if they have a job to come to," he said.

Theresa May and the Conservatives, in contrast, are clear and consistent about their Brexit policy. The prime minister will not seek to maintain the UK's full access to the EU single market, plans to broker a bespoke customs deal with the bloc and has promised to cut net migration (last recorded at 273,000) to "tens of thousands".

More details of Labour's plans are expected in the party's soon to be released manifesto. However, without clarity over Brexit, Corbyn and Starmer risk turning scores of voters off at the ballot box on 8 June.