A source at ship manager Frontline and a chartering source at Litasco both declined to comment on the fixture which has been heard to be loading in Rotterdam from March 26-28.
There were also reports of a second VLCC doing a Rotterdam-Singapore run in early April for another charterer.
Despite these fixtures being reported in the market, shipping and trading sources were unconvinced Thursday that the arbitrage was now open.
"The arb is not necessarily open," said a charterer who covers the route. "There has been a lot done recently but the fuel has got to go somewhere."
The charterer added that the cost of freight would need to be cheaper for the arb to work from their point of view. Shipping sources pegged freight rates in the $3.9-4 million range Thursday.
A shipbroker said the arb may have been open recently, but was unsure if it was currently workable. "It came pretty close to working last week, but these things change overnight," said the broker.
There was similar scepticism among trading sources. "The arb is probably not there yet. We`ve seen a few fixtures for the East but it`s probably not for real financial reasons," a trader said.
A second trading source said: "Maybe people are arbing out oil because they have to. I don`t see the arb open that much."
A shipowner provided a counterpoint to the talk of the arbitrage being closed: "It is fairly obvious it is open. There have been five VLCCs taken in the past couple of weeks."