Take a bow Sir Keir – is he Labour’s de facto leader?

But Corbyn knew he was a sharp mind – the kind that could process the intricacies of the withdrawal from the EU and maybe land a few heavy blows on the Tories.

Since his appointment he has slowly – sometimes painfully – shifted Labour to a more sensible Brexit position. When Corbyn delivers his speech today – backing the UK staying in the customs union and remaining ambiguous over the single market – it will mark the moment Sir Keir’s star truly ascended.

He has moved a Eurosceptic leadership towards a much softer Brexit – and he may even yet go further,

On the single market Corbyn will say: ‘Every country that is geographically close to the EU without being an EU member state, whether it’s Turkey, Switzerland, or Norway, has some sort of close relationship to the EU, some more advantageous than others.

‘Britain will need a bespoke relationship of its own. Labour would negotiate a new and strong relationship with the single market that includes full tariff-free access and a floor under existing rights, standards and protections.

‘That new relationship would need to ensure we can deliver our ambitious economic programme, take the essential steps to upgrade and transform our economy, and build an economy for the 21st century that works for the many, not the few.

‘So we would also seek to negotiate protections, clarifications or exemptions, where necessary, in relation to privatisation and public service competition directives, state aid and procurement rules and the posted workers directive.’

‘We cannot be held back, inside or outside the EU, from taking the steps we need to support cutting edge industries and local business, stop the tide of privatisation and outsourcing or prevent employers being able to import cheap agency labour from abroad to undercut existing pay and conditions.’