Citing unidentified sources, the US-based sport’s network’s website said Irving, who helped the Cavaliers win their first NBA crown last weekend, and Barnes, whose Warriors were on the losing end in the finals, agreed to the Brazil trip Saturday.
Australian-born Irving, Most Valuable Player of the 2014 Basketball World Cup, averaged 19.6 points and 4.7 assists for Cleveland this season.
USA Basketball is expected to unveil a Team USA roster Monday that includes Irving, Klay Thompson, Jimmy Butler, Kyle Lowry and DeMar DeRozan as guards, DeMarcus Cousins and DeAndre Jordan at centre and Kevin Durant, Carmelo Anthony, Paul George, Draymond Green and Harrison Barnes as forwards.
The US squad will be favoured to win a third consecutive Olympic gold medal in Rio under coach Mike Krzyzewski, who will leave after the games following a decade in the job. Gregg Popovich of the San Antonio Spurs is set to replace him after Rio.
The Americans will stage a training camp in Las Vegas on July 18-21 then play five warm-up games ahead of the August 6 start of the men’s Olympic tournament.