* WTI heads for fifth weekly loss
* U.S. crude output hits 28-yr high on shale oil boom
* Libya loads 2nd cargo at largest port Es Sider
* Centurion to send more oil from Permian Basin to Cushing
SINGAPORE, Aug 22 (Reuters) - Brent was trading below $103 a barrel on Friday, heading for a second weekly loss as easing geopolitical risks and higher global oil supply pressured prices.
U.S. crude production has reached the highest in 28 years due to a shale oil boom. The Organization of the Petroleum Exporting Countries pumped more oil in July despite conflicts in the Middle East and Africa.
"The market is still complacent on supply," said Ankit Pahuja, a commodity strategist at investment bank, pointing to rising oil inventories in Europe.
October Brent crude had slipped 10 cents to $102.53 a barrel by 0156 GMT.
U.S. crude was down 12 cents at $93.84 a barrel, set to post a fifth straight weekly fall.
Libya is gradually ramping up its oil production after reopening several eastern ports. It loaded a second tanker at its largest oil export terminal at Es Sider this month after being shut for a year.
"In terms of quantum, Libya is not exporting that much more oil but the market is looking at its returned supplies as it has reopened almost all of its export terminals," Pahuja said.
Libya's oil production, although still below the levels of about 1.4 million barrels per day (bpd) from a year ago, has risen to 612,000 bpd. This was well above the lows of barely 100,000 bpd seen earlier this year.
Exports from Iraq remained near record volumes despite the Islamic insurgency in the north. Crude is also exported from Iraqi Kurdistan via Turkey in defiance of Baghdad.
The United States pumped the most oil in 28 years, sending crude imports to 19-year lows, industry group American Petroleum Institute said on Thursday.
Oil inventories at West Texas Intermediate's delivery point at Cushing, Oklahoma could also rise soon as Centurion Pipeline LP has reversed a pipeline to move more oil from the Permian Basin to the Mid-West to ease a supply bottleneck.
(Editing by Florence Tan; Editing by Joseph Radford)