Vehicle owners will have to dig deeper into their pockets to buy gas during the next four weeks because prices at the pump jumped by almost 50 cents today.

This is the second month in a row that prices of petroleum products have moved upwards.

Today the price of a gallon of premium unleaded moved to $10.55, up from $10.09; the price per gallon of diesel increased from $8.04 to $8.70 and kerosene from $6.83 to $7.29 per gallon.

Meanwhile, Xinhua reported today that oil prices ended lower on Monday as Iran vowed to increase oil exports.

Iran's Deputy Oil Minister Rokneddin Javadi said that the country's crude exports would reach 2.2 million barrels per day (bpd) by the middle of summer from 2 million bpd now, according to media reports Monday.

His comments dampened hopes for a coordinated decision to freeze OPEC (Organization of the Petroleum Exporting Countries) oil production at a meeting of the exporter group in Vienna, Austria, on June 2.

In another sign that the oil market will remain oversupplied, US oil rig count stayed unchanged last week after notching an eight-week losing streak, oil service company Baker Hughes said Friday.

The West Texas Intermediate for July delivery fell 33 cents to settle at 48.08 U.S. dollars a barrel on the New York Mercantile Exchange, while Brent crude for July delivery decreased 37 cent to close at 48.35 dollars a barrel on the London ICE Futures Exchange.