Oil industry executives have gathered there for the annual Energy Intelligence Forum, with speakers including the heads of Saudi Arabia’s Aramco and Norway’s Equinor, as well as net-zero emissions minister Graham Stuart.
Five people have been arrested on suspicion of obstructing a road and taken into custody, the Metropolitan Police said.
Protesters say fossil fuel companies are deliberately slowing the global energy transition to renewables to make more profits, highlighting how the president of this year’s UN climate conference, Sultan al Jaber, is also the chief executive of the oil company Abu Dhabi National Oil Co.
Earlier, addressing reporters outside the hotel, Miss Thunberg said: “The world is drowning in fossil fuels. Our hopes, dreams and lives are being swept away by an avalanche of lies and greenwashing.
“It has been clear for decades that fossil fuel industries were well aware of the consequences of their business models and yet they have done nothing.”
The Telegraph has contacted the Metropolitan Police for comment.