fonua was first capped for tonga during a test match against samoa on 15 june 2002, in nuku'alofa. he was later called up for the 2003 rugby world cup, where he played four matches in the tournament. fonua also played rugby sevens for tonga sevens during the 2006 commonwealth games. his lastinternational test cap was during a test match against samoa, on 23 june 2007, in apia. he also played the national provincial championship for counties manukau and for southland at club level.