The Brexit deal must ensure companies can't "import cheap agency" immigrants "to undercut existing pay and conditions", the UK Labour leader has said.
Jeremy Corbyn said a future Labour government "cannot be held back inside or outside the EU" by a bad Brexit agreement during his address to the Scottish Labour conference in Dundee on Friday.
His comments come a day after the ruling Scottish executive committee (SEC) torpedoed a bid by both local party branches and former leader Kezia Dugdale to commit the party to remaining inside the European single market.
Pro-EU Labour MEP Catherine Stihler criticised the speech and said it was the party's job "to challenge anti-immigrant sentiment".
Corbyn told delegates he does not support the UK being a member of the single market in its current form, but instead wishes to see a "new and stronger relationship" struck with it.
A Brexit deal under his leadership would, he pledged, ensure "protections or exemptions where necessary from current rules and directives that push privatisation and public service competition".
He told conference delegates: "We cannot be held back inside or outside the EU from taking the steps we need to develop and invest in cutting edge industries and local business to stop the tide of privatisation and outsourcing.
"Or from preventing employers being able to import cheap agency labour, to undercut existing pay and conditions in the name of free market orthodoxy.
"It's striking that Theresa May's only clear priority when she laid out her new Brexit negotiating position last week seemed to be to tie the UK permanently to EU rules which are used to drive privatisation and block support for British industry.
"The European Union is set to make changes of its own in the coming period, especially in relation to the rules governing Eurozone economies and the rights of temporary migrant workers.
"It would therefore be wrong to sign up to a single market deal without agreement that our final relationship with the EU would be fully compatible with our radical plans to change Britain's economy.
"We are determined to negotiate a deal that gives us full tariff-free access to the single market."
Speaking after the speech, Stihler said: "Leaving the single market could cost the UK economy £45bn a year, reducing the amount of money available to governments in Westminster and Holyrood.
"And while some voters are angry about immigration, it is the job of the Labour party to challenge anti-immigrant sentiment and promote the benefits to our economy and public services.
"There is no left-wing case for leaving the European single market.