US President Joe Biden’s top aides have told the visiting Israeli defence chief that Washington is maintaining a pause on a shipment of heavy bombs for Israel while the issue is under review, a senior US official said, Reuters reports.

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

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

“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.”

The official acknowledged there have been bottlenecks in some weapons deliveries to Israel but attributed that to a complicated bureaucratic system for approving military assistance and not any deliberate slowdown.