Vessel-tracking data showed the amount of oil in floating storage was already picking up before the price war among oil producers officially began.
According to Kpler, 111m barrels were stored at sea as of 31 March, up 23m barrels from the level seen a month ago.
At least 55 dirty tankers were used as floating storage, including over 20 VLCCs, data from Braemar ACM suggested.
