Palestinians sift through the rubble after an Israeli attack on a building in the Nuseirat refugee camp in central Gaza's Deir el-Balah killed dozens of people [Abed Rahim Khatib/Anadolu Agency]

Gaza City, May 19 (RHC)-- The Israeli army has stepped up attacks across Gaza, killing dozens of Palestinians in the central part of the besieged enclave, as U.S. National Security Adviser Jake Sullivan travelled to Israel to hold talks with senior officials.

Sullivan was expected to press Israeli leaders on Sunday to take a more targeted approach in the country’s Gaza offensive and avoid a wider-scale assault on the southern city of Rafah.  He met with Israeli President Isaac Herzog and was also expected to hold discussions with Prime Minister Benjamin Netanyahu, who has vowed to move forward with the Rafah offensive despite warnings from the United States.

Nearly 800,000 Palestinians have been displaced from Rafah since Israel launched an assault on the city last week, according to the United Nations, prompting condemnations from UN officials as well as human rights groups.

The Israeli government maintains that a military operation there is necessary to destroy the last bastion of the Palestinian group Hamas.  The Israeli military has carried out intensified air and ground attacks across the Palestinian territory, with air strikes killing at least 31 people on Sunday in the Nuseirat refugee camp, in central Gaza.

Reporting from the site of the attack, Al Jazeera’s Hani Mahmoud said a residential home was destroyed while surrounding buildings “sustained a great deal of damage” and had been rendered uninhabitable.

The building, Mahmoud said, was sheltering five families who had first fled violence in the north of Gaza, and then were forced to evacuate from Rafah after Israel expanded its military operations there.  “They fled to Nuseirat only to get killed,” he said.

Israeli forces also pushed deeper into the narrow alleyways of Jabalia in northern Gaza overnight and into Sunday, returning to an area that they said they had cleared earlier in the conflict, residents said.

The Gaza Civil Emergency Service said in a statement that rescue teams have so far recovered the bodies of 150 Palestinians killed by the Israeli army in recent days, and that 300 houses had been struck by Israeli aerial and ground fire.

Sullivan’s trip to Israel – the latest by a senior U.S. official since the war broke out in early October – comes as President Joe Biden has faced widespread criticism domestically for his unwavering support for Israel amid the Gaza war.

Despite saying it disagrees with a full-scale Rafah operation, Biden’s administration has continued to provide Israel with military and diplomatic support. Last week, Washington announced plans to provide an additional $1 billion in military aid to the top U.S. ally.

Israel already receives at least $3.8 billion in U.S. military assistance annually, and rights advocates have urged the Biden administration to curb its support as the Gaza death toll continues to rise.

More than 35,000 Palestinians, mostly women and children, have been killed in Israeli attacks to date.

The humanitarian situation in the territory also has worsened since Israel seized and closed the Rafah land crossing with Egypt earlier this month.  Desperate Palestinians were filmed clambering onto aid trucks carrying supplies that were delivered through a newly U.S.-built floating pier.

The pier has been criticised as a complicated and costly alternative to what humanitarian groups say is a more appropriate and much simpler solution: for Israel to open land crossings into Gaza to allow aid trucks to deliver supplies.

“The message from all humanitarian agencies is ‘Open those crossings’ – it’s that simple,” the UN’s humanitarian affairs coordinator, Martin Griffiths, told Al Jazeera in an interview on Sunday.  “We are stuck in the south in terms of our operations because we don’t have fuel and trucks are not going through because crossings are blocked, so we have very little to offer to the people of Gaza,” Griffiths said.

Meanwhile, Netanyahu has vowed to keep fighting Hamas until the group’s military capacity is destroyed.
But the Israeli prime minister has failed to deliver a post-war plan for Gaza and to bring home the more than 100 captives still held in the enclave – and he is facing heightened political pressure inside Israel.

On Saturday, as tens of thousands of Israelis demonstrated in cities across the country, war cabinet member and former defence minister Benny Gantz threatened to quit the government should Netanyahu fail to deliver a clear six-point vision once the conflict ends.

Gantz’s warning marked one of the strongest public displays of a growing rift within the war cabinet.  It also came just a few days after Defence Minister Yoav Gallant said Israel should not be involved in governing Gaza once the fighting is over – a statement that stood in contrast to Netanyahu’s previous remarks over the need to maintain Israeli control over the territory.