Speaking ahead of Australia A's match in Nashville, Tuqiri said he admired Nawaqanitawase's courage in weighing a switch to Italy or Fiji for the 2027 Rugby World Cup, and that the former Waratah should be given time to make up his mind.
"I like the fact he's got the balls to stand on 10 toes and do what he's doing," Tuqiri said. "He hasn't made up his mind yet, has he? He should be given the time to do that."
Tuqiri, who played for Fiji and Australia in both rugby codes, said representing a heritage nation carries a strong personal pull. "There's a calling for it," he said. "It's more so the pride it gives you; it makes you puff out your chest."
The situation has divided former players. Wallabies great Matt Giteau said on the KOKO podcast: "As a proud Wallaby and a proud Australian, I want people that want to play for our country to play for our country."
NRL boss Peter V'landys has showered Nawaqanitawase with praise and signalled his desire to lure him back from Japan.
Tuqiri also questioned the decision to leave Zac Lomax, who moved from the NRL to the Western Force this season, out of the Australia A starting side. Lomax was named as a late addition to the squad but not selected for the first match against the USA.
"You can't give away Test jerseys, but Australia A is a mechanism to test players out," Tuqiri said. "I think you start him on the wing."
Australia A prop Tom Robertson described the Nashville tour as a "once in a lifetime opportunity" and said the looming World Cup added importance to the fixtures.