Vice President Kamala Harris offered Prime Minister Benjamin Netanyahu strong support for Israel’s right to defend itself from terrorism on Thursday but declared that “far too many innocent civilians” had died in Gaza and that “I will not be silent” about their suffering.

In what amounted to her debut on the world stage since her rapid ascension as the presumptive Democratic nominee for president, Ms. Harris sought to strike a balance and capture what she called “the complexity” of the strife in the Middle East. But while she did not stray from President Biden on policy, she struck a stronger tone on the plight of Palestinians.

“What has happened in Gaza over the past nine months is devastating,” she told reporters after meeting with Mr. Netanyahu at the White House complex. “The images of dead children and desperate, hungry people fleeing for safety, sometimes displaced for the second, third or fourth time — we cannot look away in the face of these tragedies, we cannot allow ourselves to become numb to the suffering, and I will not be silent.”

She noted that she had also met with the families of Israeli hostages held by Hamas since its Oct. 7 terrorist attack and expressed distress for their anguish, making a point of reciting the names of each of the hostages with U.S. citizenship. “I’ve told them each time they are not alone, and I stand with them,” she said. “And President Biden and I are working every day to bring them home.”

In a sign of the changing order in Washington since Mr. Biden withdrew from the presidential race on Sunday, Ms. Harris offered the only substantive comments after Mr. Netanyahu met separately with each of them. She pressed for the conclusion of a long-delayed cease-fire deal to end the war and bring the hostages home.

Many were watching Ms. Harris, given her new role. Over the nine months since the Hamas attack, she has largely stuck close to the president’s position, although at times she has sounded more empathetic about the suffering in Gaza, leading some to conclude that she might not be as supportive of Mr. Netanyahu’s war as Mr. Biden has been.