The UK benchmark for oil has fallen by more than 10% to around $16 (£13) a barrel.
It comes the day after the price of West Texas Intermediate (WTI), the benchmark for US oil, fell below zero for the first time ever.
The falls are a striking illustration of just how much economic activity has slowed around the world.
Prices have weakened sharply because of a combination of events triggered by a collapse in global demand.
The knock-on effect has been a supply glut and a worldwide shortage of storage space for oil.
On Tuesday energy ministers from the Opec and other major oil-producing countries held an unscheduled conference call to discuss the collapse but did not agree any new measures to cut supplies.
The price of a barrel of Brent Crude has slumped for a second day as coronavirus lockdowns hit energy demand across the globe.