Shafaq News/ Israel's partial withdrawal from the southern Gaza Strip is likely so its troops can "rest and refit," rather than a move towards a new operation, the White House said on Sunday.

"They've been on the ground for four months, the word we're getting is they're tired, they need to be refit," National Security Council spokesman John Kirby told ABC's "This Week," though he stressed that it was "hard to know exactly what this tells us right now."

Kirby spoke hours after Israel, which has been under increasing pressure from Washington over the conflict's spiraling death toll, pulled all its troops out of southern Gaza, including from the city of Khan Younis, according to the military and Israeli media.

The Israeli army said a "significant force" will continue to operate in the rest of Gaza, which it invaded after an October 7 attack by Palestinian group Hamas.

That attack resulted in the deaths of 1,170 Israelis and foreigners, most of them civilians, according to official Israeli figures.

At least 33,175 people have been killed in the Palestinian territory in Israel's retaliatory campaign, according to Gaza's health ministry.

Kirby said he would let the Israeli army "speak to their operations."

"As we understand it, and through their public announcements, it is really just about rest and refit for these troops that have been on the ground for four months and not necessarily, that we can tell, indicative of some coming new operation for these troops," he said.