Israel is withdrawing some forces from Gaza to shift to more targeted operations against Hamas, and is partially returning reservists to civilian life to help the economy as the offensive looks set to last well into the new year, an Israeli official has said.

According to Reuters, the official said toppling the group remained an objective of the offensive in the Palestinian enclave, and that some of the five brigades withdrawn will prepare for a possible flare-up of a second front against Hezbollah in Lebanon.

Israeli officials have said they would wage it in three main stages. The first was intense shelling to clear access routes for ground forces and encourage civilians to evacuate. The second was the invasion that began on Oct 27.

With tanks and troops having now overrun much of the Gaza Strip, largely asserting control despite Palestinian gunmen continuing their ambushes from hidden tunnels and bunkers, the military is moving to the third stage, said the official, who could not be named in print given the sensitivity of the issue.

“This will take six months at least, and involve intense mopping-up missions against the terrorists. No one is talking about doves of peace being flown from Shajaia,” the official told Reuters, referring to a Gaza district ravaged by fighting.

The shift appeared to correspond to pressure from Israel’s top ally, the United States, to review tactics and do more to protect non-combatants.