But overhauling more than four decades of legislation through scrapping the 1972 European Communities Act is no small task, with opposition parties already planning amendments to the Bill.

"The government cannot use the Great Repeal Bill to get their way," said the Liberal Democrats' leader Tim Farron.

"If you found the Article 50 Bill difficult, you should be under no illusion, this will be hell," he added, referring to the parliamentary debate ahead of Britain kickstarting Brexit proceedings.

Prime Minister Theresa May's government is also due to publish papers on three other major issues, after the EU's Brexit negotiator Michel Barnier urged so ahead of more exit talks next week.

"We need to know on which points we agree and on which points we disagree, so that we can negotiate in earnest," Mr Barnier said in Brussels. "We cannot remain idle as the clock is ticking."

Britain's stance on nuclear materials will be outlined, a day after the European Parliament's Brexit pointman Guy Verhofstadt said Britain cannot remain a member of the EU's nuclear regulator after Brexit.

There will also be a paper on judicial matters - a significant hurdle as London and Brussels continue to disagree on whether the European Court of Justice will still have jurisdiction.

The government will thirdly detail its view of an agreement on privileges and immunities afforded to the EU in a member country, covering areas such as property and taxes. afp