Double blow for Wallabies
Both players suffered injuries in Super Rugby at the weekend.
Centre Kerevi injured an ankle during the Reds' 29-34 loss to the Blues in Apia, Samoa, last Friday.
However, he will not require surgery.
Waratahs scrumhalf Phipps has also injured his ankle and returned home from New Zealand where the Waratahs lost 31-46 to the Chiefs this past Saturday.
Australia have called up uncapped scrumhalf Jake Gordon and his Waratahs teammate Rob Horne as replacements.
"It's really unfortunate for Samu and Nick, but a great opportunity for Jake and Rob to come into the squad," Wallabies coach Michael Cheika said.
"Jake was involved in our camp earlier this year and has really stepped up for the Waratahs in Super Rugby.
"Rob has been a strong leader in our Wallabies environment and his experience will be invaluable.
"We really want to put a strong emphasis on leadership in this team and we have some young leaders in this squad who are continuing to develop," Cheika added.
Australia kick off this month's domestic Tests against Fiji in Melbourne this coming Saturday, followed by internationals against Scotland in Sydney on June 17 and Italy in Brisbane on June 24.