Oil prices fell in Asia today, giving up some of last week's sharp gains as concerns of a global supply glut weighed on prices ahead of fresh US stocks data. US benchmark West Texas Intermediate (WTI) for delivery in February was down 27 cents, at 37.83 dollars a barrel and Brent crude for February was trading 17 cents lower at 37.72 dollars a barrel. Prices jumped last week after data showed an unexpected fall in US commercial crude stockpiles.Analysts predict the US Energy Information Administration will report another fall in US crude stockpiles on Wednesday, an indication of stronger demand in the world's top oil consumer.Oil prices have been under pressure since 2014 due to concerns about a persistent glut in world supplies and weak demand. Daniel Ang, an investment analyst with Phillip Futures in Singapore, said the end of the US export ban could make that worse by encouraging the country's shale producers to boost output. The US export ban was imposed in 1975 to protect US energy supplies after the Arab oil embargo shook the American economy.