Cash Dubai's discount to swaps widened by 50 cents to about $2 a barrel despite purchases by Chinaoil and Totsa during the Platts MoC process, traders said.
DME Oman's discount to Dubai swaps also widened by 63 cents, after touching its strongest since August on Monday, traders said.
The strong demand for Oman may also have stemmed from traders who were eyeing crude purchases by Chinese independent refiners or planning to store the grade for future sales, sources said.
Falling freight rates may have revived some interest among traders to store crude although some sources said economics barely work given that the Dubai contango structure has narrowed.
Light crude sellers remained bullish as Totsa offered March-loading Murban at 70 cents a barrel above its OSP, a trader said, up from deals at premiums of 30-40 cents previously.
Tasweeq closed on Tuesday a tender to sell March-loading condensate. Strong demand from Japan kept premiums for deodorised field condensate (DFC) near record levels earlier this month, although a trader said DFC's value is likely to ease with falling naphtha cracks.
Japan's Cosmo Oil Co said on Tuesday it had purchased a US crude oil cargo, the first by a buyer in the country since the ending of a four-decade ban on US crude exports.
Cosmo Oil is co-loading about 300,000 barrels of US crude and 700,000 barrels of US condensate in one cargo, a company spokesman said.
Separately, Iran ordered a sharp increase in oil output on Monday to take immediate advantage of the lifting of international sanctions.
Hellenic Petroleum, Greece's biggest oil refiner, will meet top Iranian oil officials on Friday to discuss crude oil imports from Iran, a company source said on Monday.
DME OMAN
DME Oman futures for March settled at $24.82, down 3 cents, at 0830 GMT. This put DME Oman at $1.02 a barrel below Dubai swaps, down from a discount of 39 cents in the previous session.
MARKET NEWS
Unseasonably warm weather and rising supply will keep the crude oil market oversupplied until at least late 2016, the International Energy Agency said in its monthly report on Tuesday.
OPEC forecast on Monday that oil supply from non-member countries will post a larger-than-expected decline this year due to the collapse in prices, boosting the need for crude from the producer group.
Venezuela's state-run company PDVSA has requested its partners in at least a half dozen joint ventures pay for naphtha imported to produce exportable crudes amid a punishing oil price crash, according to sources and a company letter seen by Reuters.
Angola plans to export 57 crude oil cargoes in March, two trade sources who has seen the loading schedules said on Monday, higher than the previous month.
China's implied oil consumption grew 2.5 percent in 2015 on strong growth in gasoline and kerosene use, defying a slowing economy and falling demand for many other commodities. Yet oil demand growth in 2016 is seen lower as the world's second-largest economy is locked in a protracted slowdown.
Petroliam Nasional Bhd (Petronas) is planning to slash spending by as much as 50 billion ringgit ($11.41 billion) over the next four years, as a slump in oil prices to multi-year lows pinches profits of the Malaysian state firm.