Nigel Farage will lead a march from Brexit-voting Sunderland to the Houses of Parliament in Westminster to campaign against the Government "betraying the British people over Brexit".
The ardent campaigner for leaving the European Union will start the 277-mile march on March 16, arriving at Westminster on March 29 - the day the United Kingdom is due to depart the trade bloc.
Although Brexit is timetabled for March 29, Theresa May’s announcement she will offer MPs a vote on blocking a no-deal Brexit or extending negotiations mean it is no longer certain the Government will take the UK out of the EU that day.
Mr Farage said: "The Westminster elite are in the process of betraying the British people over Brexit.
"All of us who want Britain to be a great country once again accept that we must be prepared to stand up for what we believe in and fight for our independence."
The march will pass through Brexit-supporting Hartlepool, Doncaster and Wellingborough on its way to the capital.
Different marchers are expected to take part in each leg of the route, leading to a mass rally in Parliament Square at its conclusion.
Leave Means Leave chairman John Longworth said: "The Westminster elite has had over two years to implement Brexit and instead has done everything in its power to prevent it.
"Despite 52% of voters choosing Brexit, only 24% of current UK MPs voted to leave.
"An extension of Article 50, thereby kicking the can further down the road, is completely unacceptable.”
Liberal Democrat MP Layla Moran, who backs the pro-EU Best for Britain, said: "This is another ludicrous idea from Britain’s best-known charlatan.
"A 14-day march sounds rough, especially one led by Nigel Farage.
"He’ll march his troops to the top of the hill where he’ll ask them to dive off the no-deal cliff edge."