The 37-year-old comes to New Zealand with a wealth of experience under his belt and will provide competition for current number one Mark Paston.
Phoenix coach Ricki Herbert, who is also in charge of the All Whites national side, is delighted to have signed such an experienced campaigner and is looking forward to him keeping Paston on his toes.
“One of the key ingredients that makes a club successful is competition for places,” Herbert says.
“We are going to have some healthy battles for first team spots throughout the team this season. It will be good for Mark to have someone experienced to work with in training.
“Mark is going really well now that he is over a bad run of injuries and the competition from Tony will do him no harm.”
Warner, who stands at 1.93m, joined hometown club Liverpool as a 16-year-old and spent nine years at Anfield but never made a first team appearance.
He was released in 1999 and headed south to join London club Millwall, for whom he made over 200 appearances and established himself as a firm fans’ favourite. A less successful spell at Cardiff City followed before he finally got his big break in the Premier League with Fulham.
During his stint at Craven Cottage he also became an international by making a sole appearance for Trinidad and Tobago.
The much-travelled custodian counts Hull City, Charlton Athletic, Leeds United and Scunthorpe United amongst his other permanent clubs and has had loan spells at numerous others.
His last run of first-team football was at Tranmere Rovers, for whom he made 25 appearances last season in League One, the third-tier of the English professional game.