Sydney - New Zealand Rugby said on Thursday it had offered Australia a deal that would allow Crusaders backrower Pete Samu to play for the Wallabies against Ireland next week.

Melbourne-born Samu is the subject of a trans-Tasman tug-of-war over Wallabies coach Michael Cheika's desire to give him an international debut for Australia, as the 2019 World Cup looms.

The highly rated 26-year-old was a notable omission when Australia's 32-man squad was announced on Wednesday for next month's three-Test series against Six Nations champions Ireland.

But Cheika said he was keeping a spot open for the flank if he received late clearance from NZR, which holds his Crusaders' contract.

NZR head of professional rugby Chris Lendrum said the New Zealanders had offered Australia a solution to the issue.

"We put a proposal to Rugby Australia early today, that would allow Pete Samu to be available for selection in June and for the Rugby Championship," he said in a brief statement late on Thursday.

"Rugby Australia is currently contemplating this proposal."

Details of NZR's proposal were not released.

Samu is eligible for the Wallabies after announcing this week that he will switch to the Brumbies next year, but he needs NZR's agreement to play under his contract with the Crusaders.

Earlier, Cheika expressed frustration at the delay in getting Samu cleared for the first Test against the Irish in Brisbane next Saturday.

"I've been told at this point I can't select him," Cheika said. "There is a spot for him there. It's in others' hands."

Crusaders chief Hamish Riach has backed Samu's bid to play for the Wallabies.

"He's Australian, he's committed to the Brumbies next year, the Wallabies want him and he's clearly going to play international rugby for the Wallabies at some point," Riach told Radio Sport in New Zealand.

"So we're quite happy for that to be sooner rather than later."

Samu has been in top form for the Crusaders this season, enticing the Brumbies to bring him back to Australia, with the club's head coach Dan McKellar calling him "a powerful backrower with good speed and a skill-set that suits how we want to play".

Samu originally played for Randwick in Sydney, before switching to Tasman in New Zealand from where he was spotted by the Crusaders and earned a Super Rugby contract in 2016.

Australia play Ireland in Brisbane on June 9, Melbourne on June 16 and Sydney on June 23.