The British public should be able to change their minds on Brexit - just as Prime Minister Theresa May did, the upper chamber of parliament heard Tuesday during a marathon debate on legislation to kick off EU negotiations.
The discussion in the unelected House of Lords was expected to last until midnight (0000 GMT Wednesday) as 190 lords planned to speak.
A second referendum on the terms of leaving the EU should not be ruled out, as people are allowed to change their minds, said politically independent peer Baron Karan Bilimoria.
Bilimoria argued that May, Chancellor Philip Hammond, and Foreign Secretary Boris Johnson all changed their minds on leaving the EU.
He echoed points made by former Labour prime minister Tony Blair in a speech on Friday, where he said leaving the EU was "not inevitable" and cited how May’s government had flip-flopped on their Brexit strategy, with Hammond previously saying leaving the single market would be "catastrophic."
May supported the remain campaign in the run-up to the referendum, but since stepping into the leadership role she has advocated a "hard Brexit" and pledged to take the country out of the European agreement which allows free movement of goods, services and people.
Johnson famously switched sides of the referendum campaign and announced his decision in a newspaper column.
May had already warned the Lords not to delay her plans to launch talks by the end of March by trying to attach conditions to the two-clause Brexit bill and throw it back to parliament's lower chamber.
But they appeared more reluctant to toe their party lines than their elected colleagues in the House of Commons, who voted to pass the bill.
Pensions expert Baroness Ros Altmann, from May's own Conservative party, said Britain's prosperity and security could be undermined as the country is led into "lighting the fuse of a two-year time bomb."
Meanwhile Lord Roger Liddle, from the opposition Labour party, criticized his own party leader Jeremy Corbyn for failing to fight May's plans, instead forcing Labour lawmakers to vote for the bill.
Baron Willoughby de Broke, from the eurosceptic United Kingdom Independence Party (UKIP), commended May's plans as laid out in her speech in late January, calling it a "UKIP speech" and said Britain had been "contracting out its laws" to Brussels for too long.
The House of Lords is more diverse than the Commons, and if its members vote to change the bill, it will kick off a parliamentary ping pong, whereby the legislation must be sent back to the lower house to be reconsidered, before returning to the upper house again.
The main topics for amendments are expected to concern securing a parliamentary vote at the end of EU negotiations and guaranteeing rights for EU citizens living in Britain.
The opportunity for the Lords to table amendments will start on February 27.