Israel's expected military invasion of Rafah in southern Gaza was the focus of President Joe Biden and Israeli Prime Minister Benjamin Netanyahu's call on Monday -- their first in more than a month -- with the White House saying Biden still has "deep concerns" Israel will not do enough to prevent civilian casualties as it goes after Hamas fighters in the city.
In the latest development in a standoff between Biden and Netanyahu that's gone on for weeks -- with the U.S. demanding a satisfactory "plan" from Israel -- national security adviser Jake Sullivan said Netanyahu, at Biden's request, would be sending a delegation to Washington to try to work out what he called "an alternative approach."
Speaking at a White House briefing, Sullivan had some of the administration's strongest words yet for how Israel has conducted itself in Gaza and how the U.S. would view an invasion of Rafah, where over a million displaced Palestinians are sheltering.
"A humanitarian crisis has descended across Gaza. And anarchy reigns in areas that Israel's military has cleared, but not stabilized," Sullivan said.
"A major ground operation there would be a mistake; it would lead to more innocent civilian deaths, worse than the already dire humanitarian crisis, deepening the anarchy in Gaza, and further isolate Israel internationally," he told reporters. "More importantly, the key goals Israel wants to achieve in Rafah can be done by other means."
Sullivan said that during Monday's call Biden "rejected" that "raising questions about Rafah is the same as raising questions about defeating Hamas."
"That's just nonsense. Our position is that Hamas should not be allowed a safe haven in Rafah or anywhere else," he said.
Sullivan also highlighted that Rafah is also a "key entry point" for humanitarian assistance that could shut down or face a "great risk" if an invasion occurs, and that Egypt has also expressed concern for a military operation there.
He announced that Israel "in the coming days" will be sending a team of officials from across many areas of government to hear the administration's concerns about the Rafah operation and to work on an alternative.
"On the call today, President Biden asked the Prime Minister to send a senior interagency team, composed of military, intelligence, and humanitarian officials, to Washington in the coming days to hear U.S. concerns about Israel's current Rafah planning and to lay out an alternative approach that would target key Hamas elements in Rafah and secure the Egypt Gaza border without a major ground invasion," Sullivan said.
Sullivan said that while Netanyahu agreed to send a team to the meeting, he "has his own point of view" on a Rafah operation.
"Send your team to Washington," Sullivan said. "Let's talk about it. We'll lay out for you what we believe is a better way."
Sullivan stressed several times that Israel needs a "coherent and sustainable strategy" for its military operations that are connected to a "clear strategic end game." He repeated the administration's public view that the White House has "every expectation" that no major military operation will happen in Rafah until the two sides meet.
At the same time, though, when pressed by ABC News' Karen Travers, Sullivan declined to say whether the Biden's call was the "come to Jesus" meeting with Netanyahu that Biden mentioned in a hot-mic moment on the House floor just minutes after his State of the Union address.
"I'm not going to characterize that on behalf of the president. I will just describe what happened in the conversation as I've done here today, and I'll let you all draw your own conclusions."
Sullivan said the leaders would stay in "close touch" in the coming days and weeks.
ABC News' Karen Travers contributed to this report.