Companies had select sellers which hurt smaller players, according to confidential reports seen by Reuters
They said the bookings, to move 4.15 million tonnes, represent additional spot tanker bookings over and above normal demand and term contracts.
"It's a huge volume, yes," one shipping broker told Reuters.
The bookings made by Vela International Marine, state oil company Saudi Aramco's chartering arm, indicate that its own large fleet is already fully employed.
Vela owns and operates one of the largest tanker fleets in the world, with 21 VLCC and ULCC-class tankers at its disposal.
Oil traders said the volume shows Riyadh will keep supplies running high into May after a sharp increase in recent months to fill shortages from Opec producer Venezuela and allay supply disruption fears ahead of a possible second Gulf War.
Saudi Arabia has raised output by more than a million barrels per day (bpd) since the start of the year and is likely to average more than nine million bpd in March of its 10.5 million bpd capacity.
Brokers said 11 of the tankers booked to load between March 27 and April 18 had so far been confirmed. It takes between five and six weeks to reach the United States from the Gulf.
Some four other Very Large Crude Carriers representing some 1.12 million tonnes of crude, booked under oil tanker pool Tankers International, were on subjects and had still to be confirmed by the charterer, brokers said.
"This is the third consecutive month Vela has come in so strongly," said Roy Mason of UK-based consultancy Oil Movements.
"It all fits with what we think we know about production changes," he told Reuters.
Shipping brokers said the huge volume had undoubtedly helped freight rates from the Gulf balloon higher. Some routes are now trading at fresh two-year highs amid brisk business and a tightening tonnage list. Freight for VLCC steaming from the Gulf to the US rose 10 points from W120 to W130 brokers said.
Companies had select sellers which hurt smaller players, according to confidential reports seen by Reuters
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