Israeli forces destroyed at least 30 residential buildings in Gaza City and forced thousands of people from their homes, Palestinian officials said, as U.S. Secretary of State Marco Rubio arrived in Jerusalem on Sunday to discuss the future of the conflict.

Israel has said it plans to seize the city, where about a million Palestinians have been sheltering, as part of its declared aim of eliminating Hamas, and has intensified attacks on what it has called the last bastion of the organization.

Rubio said Washington wanted to talk about how to free the 48 hostages still held by Hamas in the Gaza Strip and rebuild the coastal strip. Only 20 of the hostages are believed to be alive.

"What's happened has happened," he said. "We're gonna meet with them (the Israeli leadership). We're gonna talk about what the future holds," Rubio said before heading to Israel where he will stay until Tuesday.

Once there, Rubio visited the Western Wall Jewish prayer site in Jerusalem with Prime Minister Benjamin Netanyahu. 

About 300,000 flee Gaza City

About 300,000 people have fled Gaza City as Israel intensified strikes, Israel's Army Radio reported on Sunday, citing security officials.

Israeli attacks, mainly in the northern Gaza Strip, killed at least 68 Palestinians and wounded 346 others in the past 24 hours, Gaza's Health Ministry said on Sunday.

The Israeli military confirmed it had struck two high-rise buildings, claiming Hamas used them for intelligence gathering and surveillance.

Israeli army forces have been operating inside at least four eastern suburbs for weeks, turning most of at least three of them into wastelands. It is closing in on the center and the western areas of the territory, where most of the displaced people are taking shelter.

Israel says it wants civilians to leave Gaza City before it sends more ground forces in. Hamas has urged people to stay.

Aid agencies say an Israeli takeover of Gaza City would be catastrophic for a population already facing widespread malnutrition.

Two more Palestinians have died of malnutrition and starvation in Gaza in the past 24 hours, the territory's Health Ministry said on Sunday, raising the death toll from such causes to at least 422 people, including 145 children.

Gaza ceasefire mediation will continue

Qatari Prime Minister and Foreign Minister Sheikh Mohammed bin Abdulrahman bin Jassim Al-Thani said on Sunday that Israel's recent attack on Doha will not prevent Qatar, Egypt and the United States from continuing their mediation efforts to end the war in Gaza, the Qatar News Agency (QNA) reported.

According to the QNA, the Qatari prime minister made the remarks during a preparatory meeting with foreign ministers from Arab and Islamic countries, held ahead of an emergency Arab-Islamic summit scheduled for Monday to address the Israeli attack.

The foreign ministers discussed a draft statement on the Tuesday attack by Israel on a residential building in Doha that housed several Hamas leaders.

In his talks, Al-Thani stressed that the region cannot achieve comprehensive peace and security unless the Palestinian people obtain their legitimate rights.

(With input from agencies)