Australia's latest code-hopper, Israel Folau, is expected to be unveiled by the Waratahs at a media briefing on Tuesday.

The New South Wales franchise said on Monday that they will make a "major" announcement on Tuesday, but media speculation have linked Folau to the press briefing - which will make it his third switch to a different football code in four years.

The former Rugby League international and failed AFL convert is expected to announce a one-year deal with the Waratahs for the 2013 Super Rugby season.

The move is a significant coup for Australian Rugby Union, given Folau's natural talent and profile.

Folau is expected to begin training with the Tahs this week, having missed a bulk of early pre-season conditioning under new coach Michael Cheika.

Folau cut short his four-year deal with AFL franchise Greater Western Sydney last month because he was unhappy in the code, having left the NRL in 2010 as one of the game's brightest stars.

He spoke to Parramatta about joining them before he secured a release from GWS, but after advising them he would not be joining them, the Eels are now livid with Folau and will refuse to deal with him in the future.

Labelled a cash-hungry mercenary in some quarters after walking away from the protracted talks with Parramatta, Folau took to Twitter.

"Everyone is entitled to their opinions! But I'll speak the truth when it's my time," Folau tweeted.

Presumably that will happen at Tuesday's press conference.

However, the expected move has already drawn criticism from other Australian franchises, with Melbourne Rebels coach Damien Hill says he can't fathom how the Tahs could fit the code-hopper under the newly introduced salary cap.

Along with the Rebels, the 'Tahs are the only Australian franchises to have a spot to fill on their 30-man roster for next season.

But the Rebels, who were reportedly extremely close to signing Folau in 2010 before he moved to the AFL, on Monday shut the door on the possibility of recruiting the former Melbourne Storm and Brisbane Broncos centre.

"Israel is a rare talent and would be a great asset for rugby," said Hill.

"But I can't see how any Super Rugby franchises, including the Rebels, could afford him with the late timing and the salary caps that have been enforced."

A AU.5 million salary cap for each of Australia's five Super Rugby franchises has been introduced for the first time and takes effect from the start of next year as the Australian Rugby Union attempts to rein in player salaries.

A wing or centre in Rugby League, Folau would likely slot into the outside backs where the 'Tahs already boast the likes of Wallabies Adam Ashley-Cooper, Drew Mitchell, Berrick Barnes, Rob Horne and Lachie Turner while impressive youngsters Bernard Foley and Tom Kingston as well as stalwart Tom Carter also complicate selection.

Sources: The Daily Telegraph & AAP