NEW YORK: US crude neared its lowest for 2015 on Thursday after refinery outages and data indicating a large build at the key US delivery point for oil heightened worries about a global supply glut.

A rise in the dollar, after higher US retail sales in July and strengthening employment data, added to the weight on oil.

The front-month in crude futures on the New York Mercantile Exchange was down $1.10, or 2.5 percent, at $42.20 a barrel by 10:55 a.m. EDT (1455 GMT). The session low was $42.07, just above the year's bottom of $42.03 hit in March.

The front-month in global crude benchmark Brent was down 60 cents, or 1.2 percent, at $49.06 a barrel.

Brent's premium towards US crude rose to a three-week high of nearly $7 a barrel.

US crude has sank 10 percent since the start of August, adding to July's decline of 21 percent, after refinery outages added to concerns of building supplies.

Traders said repairs at BP Plc's refinery Whiting, Indiana that could last at least a month, idling some 240,000 barrels per day of crude distillation.

On Thursday, market intelligence firm Genscape reported a build of more than 1.3 million barrels at the Cushing, Oklahoma delivery point for US crude futures during the week to Aug. 11, according to traders who saw the data.

International Energy Agency said earlier that Iran could raise its oil output by as much as 730,000 barrels per day (bpd) from current levels fairly quickly after sanctions are removed, the

The West’s energy watchdog estimated that Iranian oilfields, which pumped around 2.87 million bpd in July, could increase production to between 3.4 million and 3.6 million bpd within months of sanctions being lifted.

“While significantly higher production is unlikely before next year, oil held in floating storage — at the highest level since sanctions were tightened in mid-2012 — could start to reach international markets before then,” the IEA said in a monthly report.

Iranian Oil Minister Bijan Zanganeh has said Iran expects to raise oil output by 500,000 bpd as soon as sanctions are lifted and by a million bpd within months.

Iran’s July production figures were 50,000 bpd higher than in June, the IEA said.