Hewat has missed only one match all season for the Exiles
London Irish full-back Peter Hewat has announced he will leave the club at the end of the season.
The 32-year-old Australian will continue his career with the Japanese side Suntory.
Hewat said: "The time is right for me to move on. I wouldn't play for any other club in Europe and I've always wanted to play in Japan.
"I'm looking forward to finishing the season on a high and wish London Irish much success in the future."
Head coach Toby Booth added: "Peter is a top class professional who has made a big impact at the club both in domestic and European competition.
"We're in the great position of having a talented, new generation of players such as Tom Homer, coming through our academy and player development system.
"Peter has been an exemplary role model and it is fitting that his departure creates opportunities for them to continue to grow. He leaves with our thanks and best wishes for the future."
Hewat joined London Irish from New South Wales Waratahs in October 2007.
He has played 75 games and scored 21 tries and 482 points to date.