Oil prices have edged-up towards $65 a barrel, with signs of easing supply glut concerns.
Brent crude LCOc1 increased 30 cents to $64.75 a barrel, while the US crude CLc1 gained 39 cents to $61.40, Reuters reported.
Ahead of Wednesday’s official data, the American Petroleum Institute (API) reported a decline in the US crude stocks on Tuesday.
Oil prices inched-up following an analyst poll that revealed a steady dip in the US crude stockpiles earlier in 2015.
Prices also gathered support as oil traders are raising doubts over the prospect of a deal next week on Iran’s nuclear programme.
Tokyo’s Mitsubishi oil risk manager Tony Nunan told the news agency: "US crude inventories have been at historic highs .. but the thing is, crude inventories may have peaked after oil demand picked up in June."
Nunan added saying that oil demand may increase by 1.4-1.8 million barrels per day (bpd) in June.
Iran is expected to boost exports of oil in case an agreement between Tehran and six world powers over country’s nuclear programme is reached and crude was supported by potential roadblocks for this accord.
Iran’s oil minister Bijan Zanganeh said after lifting sanctions, the country may increase oil output by 500,000 barrels per day.