The versatile back has previously played for Hull and Wigan and has been training with Canberra Raiders‘ feeder-club Down Under to keep in shape ahead of his move to Widnes.
He told the club’s official website: “I’m delighted to finally be on board. Our son was born recently back in Australia and we’ve obviously spent a fair amount of time waiting around for his passport and other necessary paperwork to arrive, but once it did, we booked the first available flight and made our way over here.
“Hopefully, if Denis thinks I’m in decent shape, he’ll include me in his plans for our game at Hull KR on Sunday afternoon.”
The Australian joined Wigan from the Canterbury Bulldogs in time for the 2008 season, and went on to score 16 tries in 48 appearances for the Warriors, before moving on to Hull for the 2011 season.
With Widnes due to play both Wigan and Hull in March, Phelps is eager to get going.
He added: “If this Sunday is out of the question, having played previously for both Wigan Warriors and Hull FC, I’ll certainly be hoping to get a run-out against them over the next couple of weeks. I’ve already missed the first 4 rounds and with a heap of big games coming up, I want to get involved and help out as soon as possible.”