Israeli tanks pushed deeper into Rafah on Tuesday, reaching some residential areas of the southern Gazan border city where more than a million people had sought shelter, and its forces pounded the enclave’s north in some of the fiercest attacks in months, writes Reuters.

Israel’s international allies and aid groups have repeatedly warned against a ground incursion into Rafah, where many Palestinians fled and Israel says four Hamas battalions are holed up. Israel says it must root out the remaining fighters.

The White House said U.S. national security adviser Jake Sullivan will visit Israel and Saudi Arabia this weekend. The Biden administration declined to comment on a report by Axios that Israel agreed not to expand its Rafah operation significantly before Sullivan’s visit.

A U.S. official who declined to be identified told Reuters that Israel promised not to make a major move in Rafah without advising Washington.

Israeli spokesperson Rear Admiral Daniel Hagari said in a briefing that Israeli forces had killed about 100 militant fighters, located 10 tunnel routes and found many weapons in Rafah since the start of the operation a week ago.

Fighting has intensified elsewhere across the Gaza Strip in recent days, including in the north, with the Israeli military returning to areas where it had claimed to have already dismantled Hamas. The clashes on Tuesday were the fiercest in months, residents and militant sources said.