The Sydney Morning Herald's website reports that White cited personal reasons for his departure after he was overlooked for the Wallabies head coach role as former Reds coach
Ewen McKenzie being selected for the job.
With 127 caps as a Brumbies player, World Cup-winning Larkham is the team's attack coach while Laurie Fisher, who was head coach between 2005 and '08, has handled the forwards under White.
Mowen said either could take on the top job.
"I would think between Bernie (Larkham) and Laurie that there's more than enough experience and direction there," said Mowen.
"Those guys have been a huge driving factor in the performance and take so much of the sessions that if it was to be in that direction it would be reasonably seamless for the group."
White, who coached the Springboks to the World Cup in 2007, had confided in his captain over the past few weeks of plans with the pair meeting in Cape Town on Wednesday.
"His importance has shifted and it's shifted to focusing on reconnecting with his two boys, Wes and Clint (White's sons)," Mowen added.
"That balanced with the fact that the Brumbies program he leaves is in a really good space and he's probably fast-tracked what he would have liked to have achieved over a four-year period into two."
"I definitely agree that the Brumbies program is in a really good spot," Mowen said,
"We missed out on the finals last year by a point and made the final this year.
"In the two years that Jake's had the team it's gone from having three Wallabies to 15 or so and he's done an enormous amount for those guys' careers to put that in place."
White has been linked to Cape Town-based Super Rugby side the Stormers.