This is an increase from the original 30,000 requested by the cabinet.
Defense Minister Ehud Barak approved the IDF's request on Friday evening to increase the maximum number of reservists it could enlist, seeking cabinet approval to mobilize up to 75,000 troops ahead of a possible Gaza ground operation.
The Inner Cabinet, a group of nine senior ministers, met for over three hours to discuss the possibility of a ground operation into the Hamas-controlled enclave, but released no statements or indications as to what transpired during the meeting.
Foreign Minister Avigdor Liberman, however, told Channel 10 that toppling Hamas is not on the agenda as a goal for Operation Pillar of Defense.
"We are definitely considering a ground operation, but toppling Hamas, I think that's something that the next government will have to decide," he said.
Liberman also told Channel 2 that the IDF will only stop its attacks against Hamas and other terrorist organizations in the Gaza Strip once Israel accomplishes its goals of stopping rocket fire and increasing deterrence.
"Each time that Hamas fires [into Israel], there will be a harsher and harsher response," he added.
Debate over invading Gaza comes after three days of constant rocket-fire from the Strip, which has reached as far as Tel Aviv and Jerusalem for the first time, and targeted Israeli strikes against terrorist leaders and weapons depots in Gaza.
On Friday morning, IDF Chief of Staff Lt.-Gen. Benny Gantz issued draft orders to 16,000 out the 30,000 reservists the cabinet approved Thursday. Most of the reservists called up thus far serve in the IDF's Engineering Corps.
The engineering corps would play a vital part in any ground operation into the Gaza Strip, enabling armored vehicles to move across the border into Gaza. The IDF operation to root out terror in the coastal territory has consisted of air raids on terror targets thus far.
The IDF would appear to have little choice but to engage Hamas on the ground. The medium range rockets that have targeted Jerusalem and Tel Aviv are difficult to hit from the air, as they are well protected. Degrading the terrorist's ability to strike deep into Israel would likely be the goal of any ground operation.
But Israel knows the likely consequences of a ground attack. The diplomatic fallout would be enormous, and with their unsteady American partner in Washington, might not get the backing they have received in the past.
Beyond that, this is the first large scale military action taken against Hamas since Egypt went Islamist and the "Arab Spring" threw up other extremist governments in the region. Egypt's President Morsi sent his prime minister to Gaza on Friday but has refrained from making direct threats against Israel. This may not last long if a ground attack materializes. The entire situation is unpredictable which is no doubt causing some hesitation by the Israelis.
In the end, they will do what they have to do to protect their citizens.