Labour leader Jeremy Corbyn has said that his party will put down an official amendment to the Article 50 bill.
If the Supreme Court allows a debate in parliament, Labour will go forward with a proposed amendment that will aim to ensure Britain maintains access to Europe's markets, workers' rights and environmental protection measures.
Speaking to Sky News, the Labour leader said: "When the Article 50 debate comes up, we will put forward an amendment to it, about market access and protections, we want those to be part of the negotiations."
Corbyn wants an amendment because he feels "there are those in the Tory party who want us to sever all connection with Europe, reduce corporate taxation, set up some kind of bargain basement trade agreement with the USA".
"The result would be a reduction in wages, reduction in public expenditure and ultimately a big reduction in living standards across Britain," he said.
He added that the party was "respecting the result of the referendum", but also refused to rule out insisting on a second referendum on the exit terms, when they are negotiated.
Denying the amendment would delay the process, Corbyn also supported the right of courts to "interpret legislation and what parliament does", saying they should be respected.
A Supreme Court hearing begins on Monday as the government aims to get an earlier judgement on Article 50 overturned.
It comes after comments from former Liberal Democrat leader Nick Clegg who said he still wants a second referendum, and the British people should bookend the Brexit process.
"We believe that since the Brexiteers didn't deign to spell out to the British people what on earth Brexit really means, and still appear unable to do so, we should give the people a say at the end of the process, so the whole process is bookended if you like, by the British people," he said.