The proposal was put forward by the military's southern command on Tuesday after a wave of attacks by Palestinian resistance fighters; but Mofaz ruled it out for the time being because of the likely complications, the Haaretz daily said.
An Israel military source declined to confirm or deny the report.
"The army does not publish its operational plans and, when it has proposals to make, it does so behind closed doors," the source told AFP.
According to Haaretz, the army plan foresaw three full brigades reoccupying two swathes of territory around the towns of Bait Hanun in the northern Gaza Strip and Khan Yunus in the south in a bid to stop Palestinian fighters attacking Jewish settlements during their evacuation.
Southern command chief General Dan Harel and Gaza commander General Aviv Kochavi set out the plans in a meeting with Mofaz. But the Israeli defence minister insisted that the Palestinian security forces were capable of halting, or at least reining in, attacks during the withdrawal, the paper said.
The defence minister also came under intense US pressure to avoid any escalation, security sources said.