Australians continue to spend more money buying online.
The National Australia Bank's latest online retail sales index shows Australians spent $13.5 billion in the year to April - up 21 per cent, or more than $2 billion, year on year.
NAB chief economist Alan Oster said online retail sales continued to grow at a vastly stronger rate than the traditional bricks and mortar retail sector.
Online sales now represent about 6 per cent of traditional retail spending, with official figures on last month's overall retail trade due on Monday.
This came as Westfield's non-executive chairman, Frank Lowy, told the annual general meeting the group was boosting its online business.
"The shopper will increasingly connect with the centre and its retailers using digital technology," Mr Lowy said.
He told the meeting the constantly changing retail landscape had always been challenging, and remained so.
"The rapid pace of change in retail formats, digital technology and shopping habits make it as difficult as ever to predict the future," Mr Lowy said.