The question was raised during a virtual fundraiser Thursday evening when Biden was asked by a donor how he would be able to replenish a number of departments that the donor said had been left "without talent" under the Trump administration, per a pool report of the event. Biden answered that the process to refill those positions is starting.

"I promise you that has already begun," Biden said. "Sounds presumptuous. I don't want to say we started thinking about it a month ago -- we did -- because that sounds like I was certain this was going to happen, that I would be the nominee. I don't want it to sound like that, but it has to happen and that's why the transition team is already being put together."

While he said he would not announce who will be leading that transition team, he noted that it would be composed of "first-rate" people. Biden also did not rule out announcing who would be nominated for some Cabinet-level positions before the November general election.

He revealed that there are discussions about elevating certain White House offices to Cabinet-level positions, like the Office of Science and Technology Policy, the global health security pandemic office and a separate climate change focus, according to the pool report.

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