BAGHDAD -- An explosion hit an Iraqi oil pipeline near the Syrian border on Monday in the second such blast in three days, posing yet another challenge to U.S. forces trying to bring order to Iraq.

In a move to boost long term security, U.S. officials unveiled plans for a new Iraqi army to replace Saddam Hussein's forces which were disbanded after the U.S.-led invasion.

"An explosion took place in the oil pipeline near the Syrian border at 1:00 a.m. (2100 GMT Sunday) last night," said an Oil Ministry official, who asked not to be named.

He had no details on the blast, which followed an explosion on Saturday that set a gas pipeline ablaze in the western desert and which Oil Ministry officials said was caused by sabotage.

The U.S. military said it was checking the report of Monday's blast, which comes as a new blow to Iraq's battered energy sector, the key to its chances of postwar recovery.

Iraq was pumping about 200,000 barrels a day of crude to Syria at preferential prices before the U.S.-led invasion. Washington bombed the line during the war to stop exports.

It is separate from Iraq's main northern export pipeline which runs from the Kirkuk oil fields to Turkey. That line was reported back in working order on Thursday after an explosion earlier this month that U.S. officials blamed on a gas leak.

Nabil Lamuza, head of planning and studies at the Oil Ministry, said the gas pipeline blast would affect gas supplies to power stations, but damage could be repaired within five days.

U.S. officials, unveiling plans for a new army, said recruiting would begin next week, but that most soldiers who served under Saddam would not get jobs.

"This country was grotesquely over-militarized," Walter Slocomb, top adviser on defense and security to U.S. administrator Paul Bremer, told a news conference.