Cummins suffered the injury to his left wrist while diving in the field during the first innings on day one of the fifth Test at the Oval on July 27. He played out the remainder of the Test match but requires a lengthy recovery. He will miss three-match T20I series in South Africa that begins on August 30 and precedes the five-match ODI series that begins on September 7.

Cummins will fly to South Africa ahead of the first ODI in Bloemfontein on September 7 but given the timeframe on his left wrist it unlikely he would be available for that first match.

Chair of selectors George Bailey sees Cummins' injury as a positive given his heavy workload during the Ashes and was confident there were enough games for him to prepare ahead of the World Cup, with Australia's first match on October 8.

"Pat injured his left wrist diving in the field on the first day at The Oval," Bailey said. "He has an undisplaced fracture of his left radius which requires six weeks rehabilitation.

"We expect him to join the squad during the South African ODI Series. We view a period of enforced rest for Pat as a positive ahead of this important World Cup campaign.

"There are still a number of games he could play before the World Cup which is more than enough for him to have a strong preparation."

Australia will trim their 18-man squad to 15 in early September with the final 15-man squad for the World Cup to be named on September 28.

Australian ODI squad: Pat Cummins (capt), Sean Abbott, Ashton Agar, Alex Carey, Nathan Ellis, Cameron Green, Aaron Hardie, Josh Hazlewood, Travis Head, Josh Inglis, Mitchell Marsh, Glenn Maxwell, Tanveer Sangha, Steve Smith, Mitchell Starc, Marcus Stoinis, David Warner, Adam Zampa