Westfield Group, the world's biggest shopping center owner by market value, said first-half operating income rose 15 percent on higher sales and rents at Australian malls.

Earnings excluding property revaluations rose to A$928 million ($797 million), or 47.8 cents a share, in the six months ended June 30 from A$809 million, or 45.3 cents, a year earlier, Sydney-based Westfield said in a statement yesterday.

Occupancy levels in Australian malls above 99.5 percent, fuelled by an economy in its 17th straight year of growth, helped Chairman Frank Lowy limit the impact of slowing consumer demand in the US. Westfield faces lower occupancy and rising rent arrears at its 55 US malls amid the worst housing slump since the Great Depression.