Qatari officials said hostages held by Hamas in Gaza have received the medication that was part of a deal brokered last month.

The Israeli Prime Minister's Office said it has asked Qatar for evidence that the medicine was delivered.

"Israel will examine the credibility of the report and will continue to work for the peace of our abductees," the office said in a statement.

The U.S. voted against a resolution calling for an immediate cease-fire at Wednesday’s United Nations Security Council meeting, The Associated Press reported.

The U.S. was the only nation of the 15 permanent Security Council members to vote against the measure, according to the AP.

U.S. Ambassador to the U.N. Linda Thomas-Greenfield said "an unconditional cease-fire without any obligation for Hamas to release hostages" was irresponsible.

"While we cannot support a resolution that would put sensitive negotiations in jeopardy, we look forward to engaging on a text that we believe will address so many of the concerns we all share -- a text that can and should be adopted by the council, so that we can have a temporary cease-fire as soon as practicable, based on the formula of all hostages being released," she said.

The U.S. has been circulating its own draft resolution on Gaza that calls for a temporary cease-fire conditioned on the release of all hostages, while also condemning Hamas for the Oct. 7 attack that sparked the war, according to senior administration officials familiar with the matter.

If the proposal were to be adopted by the U.N. Security Council, it would mark the first time the body has formally condemned Hamas’ actions.

The officials say the draft also makes clear "that under current circumstances a major ground offensive into Rafah should not proceed" and that there can be no reduction in territory in the Gaza Strip or any forced displacement of Palestinians, while also calling on Israel "to lift all barriers to the provision of humanitarian assistance, open additional humanitarian routes, and to keep current crossings open."

The senior officials signaled that American diplomats wouldn’t rush the text to a vote and that they intended on "allowing time for negotiations."

While hostage talks have sputtered over the past couple of weeks, senior administration officials said they were making some progress.

"The differences between the parties, they have been narrowed. They haven’t been sufficiently narrowed to get us to a deal, but we are still hopeful and we are confident that there is the basis for an agreement between the parties," one official said.

-ABC News' Shannon Crawford

Israeli forces, which already entered Gaza’s Nasser Hospital, are also now operating inside the nearby Al-Amal Hospital, the Israel Defense Forces confirmed to ABC News.

"Al-Amal Hospital is currently under multiple attacks, as Israeli forces have directly targeted the third floor of the hospital, resulting in the burning of two rooms," and "the hospital’s water lines were targeted," the Palestine Red Crescent Society said.

Over 8,000 patients were evacuated from the hospital earlier this month, but almost 100 patients still remain inside, the Palestine Red Crescent Society said.

The World Health Organization said Tuesday that it has helped to successfully transfer 32 critically ill patients, including two children, from besieged Nasser Hospital in the southern Gaza Strip.

The WHO said its staff led two "life-saving," "high-risk" missions at the medical complex in Khan Younis on Sunday and Monday, in close partnership with the Palestine Red Crescent Society and the United Nations Office for the Coordination of Humanitarian Affairs, "amid ongoing hostilities and access restrictions." Staff at Nasser Hospital had requested the transfer of patients after the facility became "non-functional" following an Israeli military raid on Feb. 14 after a weeklong siege, according to the WHO.

"Weak and frail patients were transferred amidst active conflict near the aid convoy," the WHO said in a statement. "Road conditions hindered the swift movement of ambulances, placing the health of patients at further risk."

"Nasser Hospital has no electricity or running water, and medical waste and garbage are creating a breeding ground for disease," the organization added. "WHO staff said the destruction around the hospital was 'indescribable.' The area was surrounded by burnt and destroyed buildings, heavy layers of debris, with no stretch of intact road."

The WHO estimates that 130 sick and injured patients and at least 15 doctors and nurses remain inside Nasser Hospital. As the facility's intensive care unit was no longer functioning, the only remaining ICU patient was transferred to a different part of the complex where other patients are receiving basic care, according to the WHO.

"WHO fears for the safety and well-being of the patients and health workers remaining in the hospital and warns that further disruption to lifesaving care for the sick and injured would lead to more deaths," the organization said. "Efforts to facilitate further patient referrals amidst the ongoing hostilities are in process."

Prior to the missions on Sunday and Monday, the WHO said it "received two consecutive denials to access the hospital for medical assessment, causing delays in urgently needed patient referral." At least five patients reportedly died in Nasser Hospital's ICU before any missions or transfers were possible, according to the WHO.

Nasser Hospital is the main medical center serving southern Gaza. Ground troops from the Israel Defense Forces stormed the facility last week, looking for members of Hamas who the IDF alleges have been conducting military operations out of the hospital. Hamas, the Palestinian militant group that governs Gaza and is at war with neighboring Israel, denies the claims.

"The dismantling and degradation of the Nasser Medical Complex is a massive blow to Gaza's health system," the WHO said. "Facilities in the south are already operating well beyond maximum capacity and are barely able to receive more patients."

-ABC News’ Morgan Winsor