Rugby league immortal Andrew Johns is set to take on a voluntary role as assistant coach for Tonga.

The former Kangaroos star is believed to have offered to help coach Kristian Woolf mentor the country’s upcoming halves when they meet Samoa in a Test on May 7.

“I just like to help out the Pacific island nations,” Johns told News Corp Australia.

“They provide so many players in the NRL and in the under-20s.

“I’ll pop into training a couple of times and and give them a hand. I’m really looking forward to it.”

Tonga lost to Samoa 18-16 in the corresponding fixture last year, with former Newcastle utility Carlos Tuimavave and Wests Tigers centre Tim Simona forming a makeshift halves pairing.

Their most recent Test was against Cook Islands last year, where fringe NRL players Pat Politoni and Daniel Foster played halves in a 28-8 win.

The Tonga-Samoa meeting is the second of a double-header to be played at Pirtek Stadium in three weeks, with Fiji and Papua New Guinea also set to face-off.