Barack Obama meets with PM in Sydney

Former US president Barack Obama has met with Prime Minister Malcolm Turnbull during a visit to Sydney for a private speaking engagement.

Mr Obama arrived at Sydney Airport at lunchtime on Friday ahead of an evening event at the Art Gallery of NSW hosted by the New Zealand United States Council.

A motorcade of vans, SUVs and more than a dozen police motorbikes, transported Mr Obama from the airport to a hotel in Sydney's CBD.

Not long after, the former US leader and his motorcade were seen visiting the Sydney Opera House.

Mr Turnbull paid a visit to Mr Obama's hotel about an hour later, spending just under two hours inside.

Mr Obama flew into Sydney from New Zealand where he met Prime Minister Jacinda Ardern and former leader John Key.

He is on a week-long tour of New Zealand, Australia, Singapore and Japan.