TEL AVIV, Israel (AP) — U.S. Secretary of State Antony Blinken on Thursday stepped up calls for Israel to comply with international law and spare civilians as it wages its war against Hamas in Gaza.

On his third trip to the Middle East since the war began on Oct. 7, Blinken said the U.S. remains committed to supporting Israel’s right to self defense. But he also said it is imperative that Israel protect civilians if it starts major military operations in southern Gaza.

His message aligns with the Biden administration’s shifting rhetoric on the war, which began as a full-throated embrace of Israel’s response to the Hamas attacks but gradually tempered as the number of Palestinian civilian casualties began to rise dramatically. The death toll and scale of destruction has prompted widespread international criticism, including from members of President Joe Biden’s Democratic Party.

Meeting in Jerusalem just hours after Israel and Hamas agreed at the last minute to a third extension of a cease-fire agreement under which Israel has paused most military activity in return for the release of hostages held by Hamas, Blinken assured Israeli Prime Minister Benjamin Netanyahu that he could count on U.S. support.

But he added that such support requires Israel’s “compliance with international humanitarian law,” and he “urged Israel to take every possible measure to avoid civilian harm.”

To prevent a further major increase in civilian casualties, Blinken said he “made clear the imperative before any operations go forward in southern Gaza there’ll be a clear plan in place that puts a premium on protecting civilians, as well as sustaining and building on humanitarian assistance getting to Gaza.”

He told reporters the Israeli government had “agreed to that approach” but declined to offer specifics on how Israel would follow through. However, he suggested that Netanyahu and others understood that that ”the massive levels of civilian life and displacement scale we saw in the north not be repeated in the south.”

Hundreds of thousands of Palestinians have sought shelter in southern Gaza after fleeing their homes in the northern part of the territory due to the conflict, and U.S. officials have been warning Israel that any offensive in southern Gaza must take into account the safety of the civilian population there.

In addition, Blinken “urged immediate steps to hold settler extremists accountable for violence against Palestinians in the West Bank” and said the U.S. places great importance on the resumption of a peace process that would eventually lead to the creation of a Palestinian state.

Israeli officials have pledged to the U.S. on multiple occasions that Israeli settler violence will be punished, but the Palestinians have complained of inaction on that front. And, Netanyahu is opposed to the creation of a Palestinian state, having told Israelis that he is the only political leader who can prevent it.

Netanyahu’s office released a statement about the meeting with Blinken that contained no mention of settler violence or a two-state solution.

Instead, in a recorded message, Netanyahu noted that his talks with Blinken had taken place shortly after a Hamas-claimed attack in which two Palestinian gunmen opened fire on commuters at the entrance to Jerusalem, killing at least three people and wounding more than a dozen others, including two U.S. citizens.

Netanyahu said he told Blinken, “This is the same Hamas that carried out the terrible massacre on Oct. 7, the same Hamas that tries to murder us everywhere. I told him: We swore, and I swore, to eliminate Hamas. Nothing will stop us.”

“We will continue this war until we achieve the three goals — to release all our abductees, to eliminate Hamas completely and to ensure that Gaza will never again face such a threat,” Netanyahu said.

Blinken met with Netanyahu and his war Cabinet in Jerusalem before traveling to the occupied West Bank for talks with Palestinian President Mahmoud Abbas and then back to Tel Aviv where he saw Israeli Defense Minister Yoav Gallant and opposition leader Yair Lapid.

In his meeting with Abbas, Blinken focused on efforts to increase the delivery of humanitarian aid to Gaza and condemned Jewish settler attacks against Palestinians in the West Bank. Blinken told Abbas “he would continue to insist on full accountability for those responsible,” the State Department said.

Blinken also told Abbas that “the United States remains committed to advancing tangible steps for a Palestinian state,” it said.

Gallant, the defense minister, repeatedly referred to the fight against Hamas as “a just war” that would not end until Israel’s goals are achieved.

“We are going to fight Hamas until we prevail no matter how long it takes,” he told Blinken. “It’s a just war. It’s a war to (defeat) Hamas, the ISIS of Gaza, and it’s a war to bring the hostages back home. As long as it takes.”

Blinken said Thursday had “started off in a very terrible and negative way with another terrorist attack that took the lives of innocent Israelis in Jerusalem, a reminder of what Israel and every Israeli citizen has to face every day.”

“We condemn it and we also mourn the loss of these innocent lives as we mourn the loss of any innocent life,” he said, adding that, at the same time, the truce had been extended.

“We want every hostage to come home,” Blinken said. “We look to see if this can continue. Certainly, that would be a good thing, and it’s also allowed much more humanitarian assistance to get in to the Gazans who need it. But it’s going to be up to Hamas whether they will continue to do this.”

The top U.S. diplomat will close out his latest Mideast tour in the United Arab Emirates on Friday, where he will discuss the Gaza situation with Arab leaders gathered in Dubai for the COP28 climate change conference.