A millionaire Tory who sits in the House of Lords argued with in his dressing gown in the street.
Andrew Fraser, made a life peer by David Cameron in 2016, confronted the climate change activists in his white gown and slippers.
Lord Fraser, 72, was a treasurer for the Conservative Party and has previously been described as a 'major donor' to the party.
It is reported he shouted at protesters in Westminster but the nature of the full exchange with the drum-banging activists is currently not known.
In photos he could be seen brandishing his fists towards them and gesticulating in his bath robe.
One plucky protester even tried to hand him a flyer for their cause.
It has been reported that Lord Fraser lives in posh townhouse on Lord North Street in Westminster.
Extinction Rebellion activists have been warned by police to move on or face arrest.
Many of those who blocked Horseferry Road overnight were warned they will be arrested unless they move to nearby Trafalgar Square, as police seek to avoid a second day's disruption which saw parts of central London virtually cut off to traffic.
Some determined activists glued themselves to the Department for Transport building in Westminster as police swept in, a tactic used during similar protests in the UK earlier this year and across the rest of the world since a fortnight of international action began on Monday.
The Met Police said it had arrested 319 people on Monday, easily surpassing the 122 arrests made on the first day of similar protests in the capital in April.
However, Scotland Yard was unable to provide further details on what people were arrested on suspicion of.
Around 200 protesters are thought to have camped in tents overnight on Horseferry Road and the surrounding area.
It came after Boris Johnson described the protesters as "uncooperative crusties", and called on them to abandon their "hemp-smelling bivouacs".
