Speaking in Australia this morning at the opening of a series of changes to the world-famous building, Utzon's son Jan spoke of a rapprochement between the Australian authorities and his father.
Utzon won a competition in the early 1960s to design the building, but famously walked away from the project in 1966 amid claims and counter claims about delays and cost over-runs.
The two sides did not talk to one another for more than three decades following the fiasco, but relations have become more cordial in recent years.
The changes to the building, masterminded by Jan Utzon and his father, include opening up the western side of the attraction with a series of large windows and doors, giving visitors views of the harbour bridge and Sydney skyline.
Speaking at an the unveiling of these alterations, Jan Utzon told the crowd that his father was disappointed he was unable to make the trip to Australia for the opening, but sent his warmest regards.
'My father, who is turning 88 next month, sends his warmest wishes and greetings to everyone here today,' Mr Utzon said. 'He and my mother are truly sad they cannot be here for the celebrations but the journey is just too much for them.
'But he feels great joy and takes much pleasure from the opening here today by Her Majesty the Queen.'
Utzon said the Sydney Opera House and Australia had been important to his family. 'Indeed, it seems to always have been part of my own life as I was only 12 when my father won the competition.
'Even after we left in 1966 the international interest in the project has always kept it alive in our family.'
Utzon said his father was pleased to reconcile differences over the building and to have the opportunity to work on it again. 'This reconciliation is also important to the architects of this style whose many years of dedicated work made the building what it is today.
'He also wishes to thank the many people who have supported him over the years, notably the famous Sydney architect Harry Seidler, who sadly passed away a few days ago,' he added.