Peers have been told to listen to the will of the country and back legislation paving the way for Brexit on January 31 after MPs voted overwhelmingly to pass the measure.
Boris Johnson’s European Union (Withdrawal Agreement) Bill cleared the Commons with a majority of 99 as the Prime Minister was able to rely on the ranks of new Tory MPs that entered Parliament at the general election.
But the legislation now heads to the upper chamber, where there is no Government majority and where peers repeatedly dealt blows to Theresa May’s administration.
In a sign of the battles that are expected to start on Monday, the Liberal Democrats – who have 94 peers – promised they would “continue to fight to hold the Government to account”.
Downing Street urged the unelected House to take heed of the December general election result which delivered Mr Johnson’s 80-seat Commons majority.
“The country did deliver a very clear message that they want Brexit to be resolved,” the Prime Minister’s official spokesman said.
Brexit Secretary Steve Barclay said he anticipated “constructive scrutiny” from peers but “I have no doubt that their Lordships will have heard the resounding message from the British people on December 12”.
“And they will have seen the clear will of this House.”
The legislation’s passage through the Commons is in contrast to the torment endured by Mrs May as she repeatedly tried and failed to get a Brexit deal through Parliament.
Liberal Democrat Brexit spokesman Alistair Carmichael said the legislation would “slash the rights of future generations to live and work” in the EU.
“As this damaging Bill progresses through Parliament, the Liberal Democrats will continue to fight to hold the Government to account and to secure the rights that the Tories are determined to erase,” he said.
The SNP’s Westminster leader Ian Blackford said Brexit would cause a constitutional crisis for the United Kingdom.
“Today will go down as the final nail in the coffin for this broken union – as Scotland faces being dragged out of the EU against our will by an extreme Tory government with no mandate here,” he said.
The legislation allows the UK to leave the EU with a deal on January 31, setting up the next stage of the process as the two sides attempt to thrash out a trade deal.
Downing Street stressed it was ready to begin negotiations on February 1.
But Brussels’ chief Brexit negotiator Michel Barnier insisted that Britain’s goal to have a full free trade deal by the end of the year was unrealistic.
“We cannot expect to agree on every aspect of this new partnership,” Mr Barnier said, adding “we are ready to do our best in the 11 months”.
He warned the UK’s market access to the EU could be limited unless it agreed to conditions on state subsidies.
“If the UK wants an open link with us for the products – zero tariffs, zero quotas – we need to be careful about zero dumping at the same time,” Mr Barnier told a conference in Stockholm.
“I hope that this point is and will be correctly understood by everybody. We will ask necessarily certain conditions on state aid policy in the UK.”