(NewsNation) — U.S. Defense Secretary Lloyd Austin and Joint Chiefs Chairman Gen. CQ Brown, who arrived in Tel Aviv on Monday, are expected to press Israeli leaders to transition to a new phase of the war after weeks of heavy bombardment and a ground offensive.

John Bolton, former U.S. national security advisor, deems the push “unfair” and inconsistent with President Joe Biden’s initial support for Israel. He highlights Biden’s acknowledgment of Israel’s objective to eliminate Hamas as a political and military force, stating it will take “as long as it takes.”

“I think this is very politically motivated. I think it has to do with the split within the Democratic Party,” Bolton said. I think as a military matter, makes no sense at all when you’re engaged directly in combat in a very complex environment like this, the idea that you can phase in time and calibrate the way we appear to be asking the Israelis to do is just unrealistic and unfair.”

American officials have called for targeted operations aimed at killing Hamas leaders, destroying tunnels and rescuing hostages. Those calls came after Biden warned that Israel is losing international support because of its “indiscriminate bombing.”

Austin is expected to press Israel on the metrics used to start the transition.

Bolton suggests a preference for less visible military activity, especially from the air. However, he notes not enough is known about Hamas’s defensive position to determine the necessary measures.

“The Israelis don’t have a better idea today in some places in the Gaza Strip than they did when this began,” he said.

Bolton added the Biden administration conveys Israel’s right to self-defense up to a certain extent; however, the international pressure aims to limit Israel’s ability to persist in its actions.

“I think they should just ignore the pressure. I think they should explain to the United States they are trying to operate within the law of armed conflict, ” he said. If the Secretary of Defense has an example where they didn’t, he should tell them, but if he’s just saying basically be a little bit more gentle and how you handle him us, I think that’s just backseat driving of the worst kind.”

Meanwhile, under U.S. pressure, Israel provided more precise evacuation instructions earlier this month as troops moved into the southern city of Khan Younis, though Palestinians say nowhere in Gaza is safe as Israel continues to carry out strikes in all parts of the territory.

Israel has reopened its main cargo crossing with Gaza to allow more aid in — also after a request from the U.S. But the amount is less than half of prewar imports, even as needs have soared and fighting hinders delivery in many areas.

Prime Minister Benjamin Netanyahu has insisted Israel will keep fighting until it removes Hamas from power, crushes its formidable military capabilities and frees the dozens of hostages still held in Gaza.

The war began with an unprecedented surprise attack by Hamas that overwhelmed Israel’s border defenses. Thousands of militants rampaged across southern Israel, killing some 1,200 people, mostly civilians, and abducting around 240 men, women and children.

The Associated Press contributed to this report.