Oil prices briefly slipped below US$56 a barrel on Wednesday, the lowest level in 5 1/2 months, as warm weather persisted throughout the U.S. Northeast amid expectations that U.S. oil reserves are sufficient for increased demand this winter, AP reported. Light, sweet crude for January delivery slipped 13 cents to US$56.37 a barrel on the New York Mercantile Exchange in Asian electronic trading, late afternoon in Singapore. Prices touched a low of US$55.72 _ a level not seen for a front-month contract since June 13. In London, January Brent crude futures on the ICE Futures exchange fell 5 cents to US$54.27 a barrel. Heating oil rose marginally to US$1.61 a gallon (3.8 liters) while gasoline was flat at US$1.3951 a gallon. --more 1303 Local Time 1003 GMT