UPDATE 1-Rugby-Prop Kepu to end Wallabies career after World Cup

* Kepu to bow out of Wallabies after World Cup

* Confident Australia has depth in front row (Adds details, quotes)

MELBOURNE, Sept 2 (Reuters) - Australia prop Sekope Kepu said on Monday he will retire from international rugby after the World Cup in Japan, bringing the curtain down on a Wallabies career that has brought him more than 100 test caps.

Kepu became just the ninth Australian test centurion when he played world champions New Zealand in Yokohama last year, and the nation's first prop to reach the milestone.

He will be honoured with a farewell ceremony in front of home fans after the Wallabies' final World Cup warmup against Samoa in Sydney on Saturday.

“It’s going to very special," 105-cap Kepu said.

"It’s another massive challenge and something I’m definitely looking forward to, running out in front of family and friends as well as our home fans for the last time this year.

"I never thought I would have achieved that milestone and to have done so, it’s something that makes me feel very privileged and fortunate."

Japan will be the 33-year-old's third World Cup before he heads to England to play with Premiership side London Irish next season.

Kepu made his test debut in 2008 against Italy in Padova and got his first start against Samoa in Sydney in 2011.

Kepu said he was leaving at a time when the Wallabies have ample depth in their front row.

"There’s guys pushing for spots everywhere now. We have quality depth in Australian Rugby and I’ll be looking from afar and just excited about what we have," he said.

"Guys like Allan (Alaalatoa) and Taniela (Tupou), they have now established themselves at test level.

"And then Scotty (Sio), Slips (James Slipper), Tolu (Latu) and Folau (Fainga’a) and all those guys – now we can play anyone in that front row and you can guarantee they are going to do the job, no matter who we are playing."

Kepu, who started at tighthead prop in the 2015 World Cup final against the All Blacks in England, has been preparing with the Wallabies in New Caledonia ahead of the Samoa test.

He said officials needed to make more of an effort to schedule tests against Pacific Island nations to grow the game.

"Yeah I think so; one test a year and it’s on a rotation,” said Kepu, who has Tongan heritage.

"I know a lot of guys playing for the Tongan team are thoroughly excited that they’re playing New Zealand and testing themselves against one of the best teams in the world," he said of the All Blacks' warmup against Tonga in Hamilton on Saturday.

“I think that’ll only help."

The Wallabies said on Monday they had flown outside back Jack Maddocks and uncapped loose forward Rob Valetini to New Caledonia to prepare for the Samoa test, with coach Michael Cheika expected to rest a number of key players.

(Reporting by Ian Ransom; Editing by Peter Rutherford)