Barry Gardiner was challenged by Julia Hartley-Brewer to explain how the Labour Party's official policy on Brexit isn't simply an attempt to "delay and thwart" the process.
Yesterday (Tuesday), the Supreme Court upheld the High Court ruling that the Government doesn't have the power to use the royal prerogative to trigger Article 50.
Legislation must be passed and a vote must be held before Theresa May can start the Brexit negotiations with the European Union.
Labour leader Jeremy Corbyn has been heavily criticised for the apparent vagueness of his approach to Brexit, although he did pledge yesterday to amend any legislation that goes through Parliament.
Gardiner, MP for Brent North and the shadow secretary for international trade, told Julia that Labour's plan is based on a desire to hold the government to account as the UK negotiates its exit from the European Union.
He said: "The referendum vote stands, but the question now is how we leave and Parliament must shape that, not just the Government.
"Our policy is to ensure the Government doesn't use Brexit as a means to turn this country into a bargain-basement, deregulated tax haven off the cost of Europe.
"They are using immigration policy to drive economic policy, and my party's view is this is wrong.
"We want a plan from the Government set out in a white paper we can use to hold them to account on, with amends, continued scrutiny and accountability throughout that period to ensure Parliament shapes the negotiations in the best interest of the people."
The conversation soon got quite tetchy, with Julia suggesting it was ridiculous for the Government to reveal its negotiating hand and undermine its chances of getting the best possible deal with Brussels.