An additional 426,000 barrels of oil storage have been added in Cushing, Oklahoma, according to US-based regulator Genscape.
Storage levels at Cushing are monitored for indication of the direction in global oil markets.
Recently, oil in storage reached exceptionally high levels, leading to a reversal in the usual price relationship between US and European crude oil prices.
Cushing operates as the delivery point for Nymex crude oil futures contracts, which makes the amount of oil available at that location of special interest to the global oil market.
Genscape supplies data on the fundamentals of coal, gas, oil and emissions in the US and Europe.