A group of MPs from the Liberal Democrats, Labour and SDLP have said they will vote against the triggering of Article 50.
Judges at the High Court ruled Parliament would have a say in when and how the process is initiated and some MPs have indicated they will vote against the bill.
Tim Farron, the leader of the Liberal Democrats, said his party would oppose Article 50 being triggered if there wasn’t a second referendum on the terms of the UK’s Brexit deal.
"It is the only logical and the only democratic option on the table. There will be a referendum at the end of this process so that nobody would have imposed upon them something they did not vote for,” Mr Farron told BBC Radio 4's Today programme.
“The clearest example, just over a week ago, is of Stephen Phillips, a Conservative MP who resigned from parliament having voted leave and being a very active leave campaigner, who said, 'Hang about, I didn’t vote to leave the single market'".
He also described the potential deal as being a “stitch-up” that no one voted for.
“We believe what started with democracy in June must not now end up as a stitch-up deal being imposed on the British people that absolutely no one voted for,” Mr Farron added.
Labour has pledged not to vote against the Government’s bill to invoke Article 50 but some MPs have indicated they will rebel, according to the BBC.
Former Labour leadership contender Owen Smith, former minister David Lammy and shadow transport minister Daniel Zeichner have all said they would defy the Labour whip.
UK news in pictures
UK news in pictures
1/19 24 June 2017
Britain's opposition Labour Party leader Jeremy Corbyn addresses revellers from the Pyramid Stage at Worthy Farm in Somerset during the Glastonbury Festival
2/19 23 June 2017
British Prime Minister Theresa May addresses a news conference at the EU summit in Brussels, Belgium, June 23, 2017
3/19 22 June 2017
Cosplay fans (L-R) George Massingham, Abbey Forbes and Karolina Goralik travel by tube dressed in Harry Potter themed costumes, after a visit to one the literary franchise's movie filming locations at Leadenhall Market in London, Britain
4/19 22 June 2017
Racegoers cheer on their horse on Ladies Day at the Royal Ascot horse racing meet, in Ascot, west of London
5/19 21 June 2017
A reveller walks among the tipi tents at the Glastonbury Festival of Music and Performing Arts on Worthy Farm near the village of Pilton in Somerset, South West England
6/19 20 June 2017
A police officer lays some flowers passed over by a member of the public, close to Finsbury Park Mosque in north London, after one man died and eight people were taken to hospital and a person arrested after a rental van struck pedestrian
The Borough Market bell is seen in Borough Market in central London following its re-opening after the June 3 terror attack
Two women embrace in Borough Market, which officially re-opens today following the recent attack, in central London
Mayor of London Sadiq Khan attends the re-opening of Borough market in central London following the June 3 terror attack
People walk through Borough Market in central London following its re-opening after the June 3 terror attack
News Corp CEO Rupert Murdoch, with one of his daughters, visit Borough Market, which officially re-opened today following the recent attack
A woman reacts in front of a wall of messages in Borough Market, which officially re-opened today following the recent attack, in central London
Vivenne Westwood walks the runway at the Vivenne Westwood show during the London Fashion Week Men's June 2017 collections
Millwall fan and London Bridge hero Roy Larner on 'Good Morning Britain'
Richard Arnold, Roy Larner, Piers Morgan and Susanna Reid on 'Good Morning Britain'
16/19 11 June 2017
England players celebrate after defeating Venezuela 1-0 to win the final of the FIFA U-20 World Cup Korea 2017 at Suwon World Cup Stadium in Suwon, South Korea
17/19 11 June 2017
England players celebrate with the trophy after the final match of the FIFA U-20 World Cup 2017 between Venezuela and England at Suwon World Cup Stadium in Suwon, South Korea
18/19 11 June 2017
Great Britain's Alistair Brownlee celebrates winning the Elite Men Columbia Threadneedle World Triathlon Leeds
Danny Lawson/PA Wire
19/19 11 June 2017
Two men drink beer outside the Southwark Tavern which reopened for business today next to an entrance to Borough Market which remains closed in London
The majority of Labour MPs are expected to either support the bill or abstain from voting - leaving it well placed to pass through the Commons.
Labour’s leader in the House of Lords, Baroness Smith, also said peers “will not block” Brexit and will instead “scrutinise” and “examine” the proposal.
“We have to be adult about this. We can’t have the most enthusiastic Brexiteers crying foul every time Parliament asks for more details or seeks to scrutinise,” she said.
Brexit Minister David Jones said: "Parliament voted by a margin of six to one to put the decision on whether to remain in, or leave, the EU in the hands of the British people.
"Now, because they didn't like the first answer, Liberal Democrat and Labour MPs seek to put the question all over again in hope of a different answer.
"They are attempting to thwart and reverse the decision that was taken on June 23.
"Only the Conservatives can be trusted to respect the outcome of the referendum and make a success of Brexit."Reuse content