The high court has ruled the government will not be able to bypass parliament to trigger Article 50 of the Lisbon Treaty.
In defending her decision to use the Royal Prerogative, Theresa May says the will of the people is represented in the referendum and as such, should be respected without being put to a parliamentary vote.
Lord chief justice, Lord Thomas of Cwmgiedd declared "The government does not have power under the Crown's prerogative to give notice pursuant to Article 50 for the UK to withdraw from the European Union."
He continued to describe the argument of the government to be "contrary to fundamental constitutional principles of the sovereignty of parliament." and added no part of the 1972 Act supported it.
A Government spokesperson has quickly announced "The country voted to leave the European Union in a referendum approved by Act of Parliament. And the government is determined to respect the result of the referendum. We will appeal this judgement."
The appeal is set to be heard sometime next month.
Last month, Theresa May said she intended to trigger Article 50 by March 2017. Depending on the outcome of this appeal, it will potentially be delayed for months as the Parliament considers the terms for #Brexit.
UKIP leader Nigel Farage expressed his anger on twitter, saying "Last night at the Spectator Parliamentary Awards I had a distinct feeling that our political class, who were out in force, do not accept the 23rd of June referendum result
"I now fear every attempt will be made to block or delay triggering Article 50. They have no idea level of public anger they will provoke."
BBC's assistant political editor Norman Smith has mentioned if the Parliament were to vote, it is likely that most MPs would likely vote for leave as it is in the governments interest to follow the will of the people.
However, once it is put to Parliament, it is likely there would be a far more restrained approach to delineating the conditions of brexit, decreasing the likelihood of a hard Brexit.
The court ruling has had an immediate effect on the pound as it rose 1% against the dollar. For the first time in three weeks, sterling reached $1.24 but has since dipped back down to $1.23.