Her predecessor Vince Cable said that if a new ‘version’ of Theresa May’s rejected deal gets support in the Commons, the Lib Dems must insist on a second referendum as a condition.
The party faithful has descended upon Bournemouth’s seafront as conference season kicks off in a relentlessly fractious time in British politics.
While Boris Johnson looks to weather the storm after Scottish judges this week ruled his advice to the Queen to suspend Parliament was unlawful, the Lib Dems are looking to capitalise and mobilise supporters in Dorset in preparation for a snap election.
Parliament has so far denied Johnson’s request for an autumn trip to the polls after opposition parties and Tory rebels passed legislation requiring the PM to extend the Brexit deadline until 2020.
With Royal Assent for the Benn-Burt bill now achieved and no majority in the House of Commons for the PM, both the Conservative Party and its rivals are gearing up for another Brexit-themed election.
Swinson wants to sign her colleagues up to the policy of revoking Article 50, which would cancel the divorce from Brussels without the need for a second referendum.
The move to undo the mechanism under the EU’s Lisbon Treaty which triggered the UK’s withdrawal would be in the next Lib Dem election manifesto if members support it.
The Labour Party policy would involved renegotiating a deal with Brussels and putting it to a confirmatory vote, should the party win the next general election.
Veteran British diplomat Lord John Kerr, who was involved in drafting Article 50, has publicly said the clause is reversible.
Swinson said: ‘We got into this mess as a result of having a referendum in the first place and that (revoking Article 50) is the only satisfactory way out of it.’
The party leader is due to take questions from conference attendees at the Bournemouth International Centre tomorrow following a speech by her predecessor Sir Vince Cable.
Speaking today, Sir Vince said Conservative and Labour MPs could vote for a version of the deal, but that the Lib Dems would insist any deal must be subject to a referendum with an option to remain.
He added: ‘It does put us into new political territory. I think we have to prepare for it mentally and emotionally.’
The East Dunbartonshire MP will close the four-day conference with a speech on Tuesday, with a tribute to former leader Paddy Ashdown, who died in December.
Swinson has played an active part in convincing MPs to switch allegiance and join the Lib Dems – with six joining the party over the past six months.
Ex-Tories Philip Lee and Sarah Wollaston and former Labour and Independent Group members Luciana Berger and Angela Smith defected in recent weeks.
Chuka Umunna, who joined the Lib Dems under Sir Vince’s leadership, will address party members on Monday in his role as Treasury and business spokesman.