The latest round of Gaza cease-fire talks ended in Cairo after “in-depth and serious discussions,” the Hamas officials said Sunday, reiterating key demands that Israel again rejected as too lenient on the terrorist group.

After signs of progress, the outlook appeared to dim as Israel closed its main crossing point for delivering badly needed humanitarian aid for Gaza after Hamas attacked it. The defense minister claimed Hamas wasn’t serious about a deal and warned of “a powerful operation in the very near future in Rafah and other places across all of Gaza.”

Israel didn’t send a delegation to the talks mediated by Egypt and Qatar, and Defense Minister Yoav Gallant said that “we see signs that Hamas does not intend to go to any agreement.”

Egyptian state media reported that the Hamas delegation left Cairo for discussions in Qatar and will return to the Egyptian capital for further negotiations on Tuesday.

Another threat to talks came as Israel ordered the local offices of Qatar’s Al Jazeera news network to close, accusing it of broadcasting anti-Israel incitement. The ban did not appear to affect the channel’s operations at Gaza.

In another sign of strained relations between the Biden administration and Prime Minister Netanyahu’s government, Axios reports Sunday that American officials last week put a hold on new munitions shipments to Israel. The move would mark the first such stoppage since the October 7 attacks last year.

Mr. Netanyahu, under pressure from hard-liners in his government, continued to lower expectations for a cease-fire deal, calling the key Hamas demands “extreme” — including the withdrawal of Israel forces from Gaza and an end to the war. That would equal surrender after the Hamas attack on October 7 that triggered the fighting, Mr. Netanyahu said.

Mr. Netanyahu again vowed to press on with a military operation in Rafah, the southernmost Gaza city on the border with Egypt where more than half of Gaza’s 2.3 million residents are now sheltering from Israeli attacks. Rafah is a key entry point for aid.

Kerem Shalom, now closed, is another crossing. The Israeli military reported 10 projectiles were launched at the crossing in southern Israel and said its fighter jets later struck the source. Hamas said it had been targeting Israeli soldiers in the area. Israel’s Channel 12 TV channel said 10 people were wounded, three seriously. It was unclear how long the crossing would be closed.

The proposal that Egyptian mediators had put to Hamas sets out a three-stage process that would bring an immediate, six-week cease-fire and partial release of Israeli hostages taken in the October 7 attack, and would include some sort of Israeli pullout. The initial stage would last for 40 days. Hamas would start by releasing female civilian hostages in exchange for Palestinian prisoners held by Israel.

Mr. Netanyahu claimed that Israel has shown willingness to make concessions but said it “will continue fighting until all of its objectives are achieved.” That includes the stated aim of crushing Hamas. Israel says it must target Rafah to strike remaining fighters there despite warnings from the United States and others about the danger to civilians.

In later remarks for Israel’s annual Holocaust memorial day, Mr. Netanyahu added: “We will defend ourselves in every way. We will overcome our enemies and we will ensure our security — in the Gaza Strip, on the Lebanese border, everywhere.”