Defense Minister Yoav Gallant met with CIA chief Bill Burns, the key US pointman in negotiations to free hostages from Hamas, and later met for around two hours with Secretary of State Antony Blinken.
"I would like to emphasize that it is Israel's primary commitment to return the hostages, with no exception, to their families and homes," Gallant said before starting his meetings.
"We will continue to make every possible effort to bring them home," he said.
He made no further comment as he left the meeting with Blinken, as a couple of dozen protesters outside the State Department chanted to call him a "war criminal."
President Joe Biden on May 31 laid out a plan for a ceasefire in Gaza and release of hostages, ahead of talks on ending the war.
Hamas, which launched the conflict with its October 7 attack on Israel, has come back with its own demands, and the United States hopes the gaps can be bridged.
Israeli Prime Minister Benjamin Netanyahu, who has faced major protests calling for him to accept the deal, in recent days has annoyed the Biden administration by accusing Washington of cutting back arms and ammunition deliveries.
Gallant took a different tack, saying, "The alliance between Israel and the United States, led by the US over many years, is extremely important."
Other than Israel's own military, "our ties with the US are the most important element for our future from a security perspective," he said.
Biden, who has faced criticism from parts of his own base over his support for Israel, held back a shipment that included heavy 2,000-pound bombs.
Netanyahu -- who has close relations with Biden's rivals in the Republican Party -- told a cabinet meeting on Sunday that there was a "dramatic drop in the supply" of US weapons around four months ago.
Asked about his latest comment, State Department spokesman Matthew Miller said, "I don't understand what that comment meant at all."
"We have paused one shipment of high-payload munitions. That shipment remains on pause," Miller told reporters.
"There are other weapons that we continue to provide Israel, as we have done going back years and years, because we are committed to Israel's security. There has been no change in that," Miller said.
Gallant said he would also discuss the next phase of the war after Netanyahu said that the "intense" fighting with Hamas in Rafah was "about to end."
Miller said the United States would press Israel to work on longer-term arrangements after the end of the fighting.
"We don't want to see in Rafah what we've seen in Gaza City and what we've seen in Khan Yunis, which is the end of major combat operations and then the beginning of Hamas reasserting control," he said, referring to two other major cities targeted by Israel earlier in the war.
Gallant is also expected to meet in Washington with Defense Secretary Lloyd Austin, senior White House official Brett McGurk and Amos Hochstein, who is focusing on tensions over Lebanon.
