LONDON (AP) -- Britain's key piece of Brexit legislation is starting a new battle in Parliament, as the government downplays a leaked internal document saying leaving the European Union will hurt the U.K. economy.
The House of Lords on Tuesday began scrutinizing the EU Withdrawal Bill, which is designed to convert thousands of EU laws into British statutes when the U.K. leaves the bloc in March 2019. Without it, Britain could face a legal black hole after Brexit.
A majority of members of Parliament's unelected upper house oppose Brexit, and will try to amend the legislation.
Meanwhile, an assessment prepared for the government and leaked to news site BuzzFeed forecasts that Brexit will leave the economy between 2 percent and 8 percent worse off, depending what trade deal Britain strikes with the EU.