Mr Batten and Mr Robinson – real name Stephen Yaxley-Lennon – will be giving speeches from a stage with a “sound system loud enough that Theresa May will be able to hear every single word in 10 Downing Street”.
The far-right Democratic Football Lads Alliance will also be holding a demo in Parliament Square from 4pm.
The “yellow vests” are also reported to be holding a rally in the capital.
These demonstrations will be met with counter-protesters.
The Met rejected a claim by Mr Batten that a water cannon will be deployed at all the pro-Brexit protests.
It said on Friday: “Those reports are indisputably false.”
Separate pro-Brexit protests will also be held by the Leave Means Leave campaign, while former Ukip leader Nigel Farage – who resigned from the party over its appointment of Mr Robinson – is set to greet the “March to Leave” as it arrives in Parliament Square at 4pm.
Walkers had set out from Sunderland two weeks ago.
It comes on the day when Theresa May puts her Withdrawal Agreement before Parliament once more.