JEREMY Corbyn has insisted Labour is on the cusp of a major comeback in Scotland – before appearing to forget how many MPs he has north of the border.

The UK Labour leader will address the party faithful at Scottish Labour’s conference today, where he will say he is “preparing to go into government”.

But in extracts released ahead of the speech, he said: “We won six seats for Scottish Labour at the last general election, and we are on the cusp of winning in around 20 more.”

Scottish Labour won seven seats at last year’s election. Six were newcomers, but Ian Murray – a prominent critic of Mr Corbyn – kept hold of Edinburgh South.

Scottish Conservative deputy leader Jackson Carlaw said the blunder “shows exactly how much attention Mr Corbyn pays to events north of the border”.

It comes as Scottish Labour is expected to call for a “whole scale review of public procurement” in the wake of Carillion’s dramatic collapse earlier this year.

Figures obtained by the party show the outsourcing giant’s contracts with public sector agencies in Scotland were worth at least £630 million at the time it went under.

More than 250 workers were directly employed on its Scottish projects – and many more are thought to have been drafted in via sub-contractors.

Scottish Labour economy spokeswoman Jackie Baillie MSP said the “truly astonishing figures” revealed the extent of Carillion’s involvement in Scotland.

She said: “SNP economy minister Keith Brown has tried to convince us everything is fine, when the clear reality is that he has been sleepwalking into a crisis.”

She highlighted “truly shocking stories” of exploitation, with workers contracted on Carillion projects claiming they were forced to work zero hours contracts – while umbrella companies charged them up to £100 to collect their wages.

One rail worker at Waverley Station, where the firm was responsible for platform extensions, said: “Since the collapse of Carillion the regular work I was getting has dried up. I have been going without work for days and weeks at a time.”

Carillion’s Scottish projects included a £533 million contract to deliver the new Aberdeen bypass. Economy Secretary Keith Brown previously said more than 90 per cent of the firm's Aberdeen employees would move to other contractors following its collapse.

Stevie Dillon, from Unite the union, called for an end to the outsourcing of public sector contracts.

Scottish Labour faces ongoing splits over its approach to Brexit as it meets for its conference in Dundee this weekend.

Prominent party figures – including Ian Murray – have urged it to throw its weight behind remaining in the single market, and a debate on the issue is expected on Sunday morning.

Addressing delegates today, Mr Corbyn will insist Labour will fight for a Brexit deal “that prioritises jobs and living standards”.

He will also pay tribute to Scottish leader Richard Leonard “for the work he has done preparing a movement to oppose any visit by US President Donald Trump to Scotland”.

He will add: “While the SNP wooed Trump to build his golf course in Aberdeen, and Theresa May appeases him as she bets the UK economy on a race-to-the-bottom trade deal with the US, Richard has shown Labour is standing up to oppose the racism, misogyny and dangerous belligerence coming from the US administration.”

SNP MSP George Adam said Scottish Labour’s internal Brexit splits would be the “elephant in the room”.

Meanwhile, a Scottish Liberal Democrat spokesman mischievously suggested Mr Corbyn's pre-conference gaffe was a snub to Mr Murray.

He said: “We knew that Ian Murray standing up for the vast majority of Labour members who want to remain in the single market would not be popular with the Labour leadership but we hadn’t realised it would have him struck off Commissar Corbyn’s list in quite such a dramatic fashion.”