NRL premiership hero Nathan Cleary has declared his support for the Voice to Parliament in a video posted to social media just hours after he led Penrith to their third consecutive grand final win.

Cleary, also the national side's halfback and NSW representative, employed Australians to back the proposal less than a fortnight from the referendum.

"No Voice, no choice. Come on Australia, vote yes," Cleary said.

The short video was posted to social media accounts of former NSW Aboriginal Land Council chairman, former Indigenous Advisory Council member under Malcolm Turnbull and Indigenous Business Australia board member Roy Ah-See.

Ah-See had made a presentation to the Panthers about misinformation surrounding the Voice in recent weeks, alongside other clubs.

Cleary is said to have asked how he could help support the Yes campaign.

"He said I'll do anything. He said he wanted to live in a better country which was inclusive for everyone, and he felt strong about it," Ah See said, via The Age and Sydney Morning Herald.

"This young man, I'm just so proud of him. They are leaders in their space and what they do," he said.

The 25-year-old is wearing an Uluru Statement t-shirt in the video posted by Ah-see.

The gesture was shared shortly after Cleary scored the winning try in Penrith's 26-24 comeback win over Brisbane in the 2023 NRL Grand Final on Sunday.

It's a rare high-profile display of individual support for the Voice by a current sportsperson, despite all major football codes in the country officially backing the proposal in recent months.

Prime Minister Anthony Albanese later reposted the video.

The Voice referendum is set for October 14.