June 30 (Bloomberg) -- Crude oil traded little changed, poised for its biggest quarterly gain since 1990 before a report tomorrow expected to show an increase in U.S. gasoline stockpiles.

Gasoline inventories in the U.S. probably climbed 2 million barrels in the week ended June 26 from 208.9 million the previous week as refineries increased production, a Bloomberg News survey showed. Oil fell back after climbing as much as 2.6 percent as a weaker dollar drove investors to commodities as a hedge against inflation and Nigerian rebels attacked oil installations. Prices rose 3.4 percent yesterday.

“The prospect of product stock builds in the U.S. statistics report and yesterday’s speculative buying drying up is pushing oil prices lower,” said Christopher Bellew, senior broker at Bache Commodities Ltd. in London. The influence of supply disruptions in Nigeria is waning, he said.

Oil futures have gained 44 percent this quarter on optimism that the global economic recession is easing. That’s the biggest gain since the third quarter of 1990, when they more doubled after Iraq’s invasion of Kuwait.

Oil for August delivery traded at $71.16, down 13 cents, or 0.2 percent, in electronic trading on the New York Mercantile Exchange at 12:41 p.m. London time. It earlier rose as high as $73.38 a barrel.

U.S. refineries operated at 87.2 percent of capacity last week, up 0.1 percentage point from the previous week, according to the survey of nine analysts. Operating rates rose 1.2 percentage points in the week ended June 19 to the highest level this year.

Brent crude oil for August settlement declined as much as 64 cents, or 0.9 percent, to $70.35 a barrel on London’s ICE Futures Europe exchange and traded at $70.72 at 12:38 p.m. local time. Yesterday, it climbed $2.07, or 3 percent, to $70.99 a barrel, the biggest gain since June 4.

To contact the reporters on this story: Alexander Kwiatkowski in London at akwiatkowsk2@bloomberg.net.

Last Updated: June 30, 2009 08:15 EDT