limate group Just Stop Oil said 51 of its supporters are disrupting seven petrol stations across London.
In some locations, activists rendered fuel pumps unusable by breaking their display glass or covering them with spray paint.
At others they blocked access by sitting on the road with banners.
The action started at around 6am.
The Metropolitan Police said it made five arrests after an incident at a petrol station in west London.
A spokesman said: “Police were called at 6.29am on Friday to reports of protesters damaging pumps at a petrol station in Talgarth Road, Hammersmith.
“Officered attended and within approximately 10 minutes had arrested four men and one woman on suspicion of criminal damage.
“They remain in custody at a west London police station. Inquiries are ongoing.”
Just Stop Oil has repeatedly protested against new oil projects in recent days, including at service stations on the M25 motorway.
Tez Burns, 34, a bicycle mechanic and physics graduate from Swansea taking action on Friday, said: “I can’t live with myself, knowing what I know, without doing all I can to stop new oil and gas.
“We are suffering the worst cost-of-living crisis in 40 years and facing climate breakdown because of our dependence on oil.
“Yet the Government is allowing energy companies to drive us into poverty with skyrocketing energy bills, and is failing to protect us from the consequences of climate collapse. Enough is enough.”