Billionaire Kerry Stokes and his wife Christine Simpson Stokes have made a surprise visit to Canberra to commemorate Anzac Day at the Australian War Memorial after the WA government granted them exemptions from hotel quarantine on medical grounds.

The couple finished their 14-day self-isolation at their riverside Perth mansion on Wednesday after returning from the United States by private jet on April 8.

Chair of the Australian War Memorial Kerry Stokes and Christine Simpson Stokes lay a wreath at the Tomb of the Unknown Australian Soldier in Canberra on Saturday morning. Credit:Alex Ellinghausen

Mr and Mrs Stokes flew to Canberra on Friday and will travel on to Sydney despite Western Australia's strict "hard border" closures that mean they will not be able to return to the state without the government granting more exemptions to its travel rules.

The pair attended the Anzac Day service where they laid a wreath along with Governor General David Hurley and Prime Minister Scott Morrison.