The former Highlanders captain has just completed his first season at Italian side Treviso after two years with Edinburgh.
The 29-year-old is one of six new caps in the team to contest the Pacific Nations Cup in Fiji.
Nasi Manu said he is excited to get the chance to represent his family.
"My parents were born in Tonga and they obviously moved [to New Zealand] for better opportunities for us [kids]," he said.
