The United States urged swift action and flexibility in finalizing a cease-fire agreement between Israel and Hamas, following the deaths of six hostages in Gaza.

"There are dozens of hostages still remaining in Gaza, still waiting for a deal that will bring them home. It is time to finalize that deal," State Department spokesman Matthew Miller told reporters on Tuesday.

"The people of Israel cannot afford to wait any longer. The Palestinian people, who are also suffering the terrible effects of this war, cannot afford to wait any longer. The world cannot afford to wait any longer," Miller said.

Miller said that the United States will work "over the coming days" with mediators Egypt and Qatar "to push for a final agreement."

One key sticking point has been Israeli Prime Minister Benjamin Netanyahu's insistence that Israeli troops remain at the border between Gaza and Egypt.

"We are opposed to the long-term presence of IDF troops in Gaza," Miller said, referring to the Israel Defense Forces.

Progress was made on the remaining obstacles during talks last week, Miller told reporters but said reaching a deal will require flexibility on both sides.

Miller said the U.S. would continue to engage with regional partners over the coming days to finalize the deal.

On Monday, President Joe Biden said Israeli Prime Minister Benjamin Netanyahu was not doing enough to reach a deal for the release of hostages held by Hamas.

The United States, along with fellow mediators Egypt and Qatar, has spent months pushing for a hostage-prisoner exchange and cease-fire in the war in Gaza.

Hamas seized 251 hostages during the Oct. 7 attack on Israel, 97 of whom remain in Gaza, including 33 the Israeli military says are dead.

Scores of hostages were released during a one-week truce in November.

An Israeli court on Monday ordered a halt to a strike called by the country's largest union aimed at ramping up pressure on Netanyahu's government to secure the release of the remaining captives.

Hostage relatives and advocates have accused Netanyahu's administration of not doing enough to bring the captives back alive, and have called for an immediate ceasefire.

More than 40,786 Palestinians, mostly women and children, have been killed in Israel's military campaign in the Gaza Strip since the war began.

Most of the dead are women and children according to the U.N. human rights office.