Shopping centre group Westfield has said that it is planning to spin off its Australia and New Zealand businesses into a new company, merged with Westfield Retail Trust.

The new business will be separate from the group’s UK and US assets and the two businesses will be listed separately as well as having separate boards and managements.

"Westfield's international business and its Australian/NZ business have both grown in scale and quality to the stage where they can now stand on their own," Westfield Chairman Frank Lowy said in a statement.