Boris Johnson has asked the Queen to suspend Parliament, but he rejected claims the reason was to block MPs from thwarting a no-deal Brexit.
The suspension will come just days after MPs return to Parliament after the summer recess, giving them limited time to pass laws to stop a no-deal Brexit on October 31.
The Prime Minister said it was "completely untrue" that Brexit was the motivation for proroguing Parliament.
He insisted it was time for a new session of Parliament to set out his "exciting agenda".
However the move has been met with a strong chorus of condemnation, including from Commons Speaker John Bercow, who labelled it a "constitutional outrage."
Shadow chancellor John McDonnell said: "Make no mistake, this is a very British coup.
"Whatever one's views on Brexit, once you allow a Prime Minister to prevent the full and free operation of our democratic institutions you are on a very precarious path."
While senior Tory backbencer Dominic Grieve called the move "an outrageous act".
So where do Wednesday's events leave the Brexit timeline?
- September 3
The House of Commons resumes on September 3, as MPs return to the debating chambers after the summer recess.
Hundreds of MPs had urged Mr Johnson to recall Parliament early over the "national emergency of Brexit".
But he ignored the letter, which was signed by every political party in the House of Commons, except the DUP.
MPs will have just over a week to debate Brexit, before the planned suspension.
Opposition parties had agreed to work together on passing legislation to block a no-deal Brexit when the Commons resumes sitting on September 3.
- September 10
Under the Prime Minister's plan, Parliament will be temporarily shut down from around September 10.
Parliament is likely to begin the process for prorogation on September 9.
The move has led to accusations Mr Johnson is acting like a "tin pot dictator" and dragging the Queen into a bitter constitutional row, as she is the only one with the power to suspend Parliament.
- September 29 - October 2
Mr Johnson's move will make sure the Commons is not sitting during the party conferences.
The Tory conference is due to start on September 29 and finish on October 2, while Labour's will start on September 21 and end on September 25.
- October 14
The Prime Minister will hold a Queen's Speech on October 14, after the suspension.
MPs will return to the Commons for the state opening of Parliament.
- October 17 and 18
A crunch EU Council summit will be held on October 17 and 18, the final EU summit before Brexit.
This might be the last opportunity the Prime Minister has to avoid a no-deal Brexit and break the impasse.
In a letter to MPs, Mr Johhnson said EU leaders were watching the actions of MPs: "These weeks leading up to the European Council on 17/18 October are vitally important for the sake of my negotiations with the EU.
"Member states are watching what Parliament does with great interest and it is only by showing unity and resolve that we stand a chance of securing a new deal that can be passed by Parliament."
- October 31
The current Brexit date, as it stands.
Mr Johnson has repeatedly said the UK will leave the EU on October 31 with or without a deal.