The official, briefing reporters about national security adviser Jake Sullivan's meeting with Defense Minister Yoav Gallant, said the allies remain in discussions about the single shipment of powerful munitions, which was paused by Biden in May over concerns they could cause more Palestinian civilian deaths in Gaza.

Without providing specifics, the official said other U.S. weapons will continue to flow to Israel as it battles Hamas militants in Gaza and faces Lebanese Hezbollah fighters on its northern border, where escalating hostilities have spurred fears of a wider regional conflict.

Wrapping up his visit, Gallant said earlier on Wednesday that there had been significant progress on the issue of U.S. munitions supply to Israel, adding that "obstacles were removed and bottlenecks were addressed."

Gallant and U.S. officials sought to cool tensions following Prime Minister Benjamin Netanyahu’s recent claims that Washington was withholding weapons, prompting Biden's aides to express disappointment and confusion over the Israeli leader’s remarks

The United States in May paused a shipment of 2,000-pound and 500-pound bombs due to concern over the impact they could have in densely populated areas in Gaza in the war against Hamas, but Israel was still due to get billions of dollars worth of U.S. weaponry.

"We are in discussions ultimately to find a resolution," the senior U.S. official said on condition of anonymity. "But I think the president has expressed his concerns about that one shipment, and those are very valid concerns,"

ISRAEL-LEBANON BORDER

Gallant also discussed with Sullivan "Israel's commitment to ensuring the safe return of Israeli communities to their homes in the north by changing the security reality in the area," the Israeli defense chief's office said.

Gallant on Tuesday met with Defense Secretary Lloyd Austin, who said the U.S. was working urgently in pursuit of a diplomatic agreement to calm the situation on the Israel-Lebanon border between Israeli forces and Iran-backed Hezbollah fighters.

An exchange of shelling and missile strikes has led to the evacuation of tens of thousands of people on both sides of the border, and escalation has sparked fears of an all-out war in the area.

"Nobody that we have talked to, Lebanon, Israel, wants a major escalation that is not in anybody's interest, not in our interest," the senior U.S. official said on Wednesday.

Gallant’s talks in Washington also focused on Iran, Israel’s regional arch-foe. He discussed with Sullivan the importance of cooperation "vis-a-vis Iranian aggression and its nuclear ambitions," Gallant's office said.

While Israel has expressed increasing alarm over Iran's nuclear program, the senior U.S. official cited intelligence assessments that Tehran is not "currently pursuing the procedures and processes they would need to develop an explosive nuclear device."

But the official added that Iran had taken some "provocative steps" recently that would not go unchallenged.

The U.S. and Israel, the official said, are working to reschedule a strategic dialogue on Iran. A meeting set for last week was scrapped following Netanyahu's criticism.

Iran says its nuclear program is solely for peaceful purposes.