Israeli Prime Minister Benjamin Netanyahu attended a ceremony at the "Iron Swords" monument in Jerusalem to commemorate Israelis killed since Oct. 7, 2023.

The monument was unveiled in September to remember those from Jerusalem killed during Hamas' Oct. 7 attack on southern Israel and in the subsequent fighting.

"On this day, in this place, and in many places in our country, we remember our fallen, our abductees -- whom we are obliged to return -- and our heroes who fell for the defense of the homeland and the country," Netanyahu said.

"We went through a terrible massacre a year ago and we stood up as a people, as lions."

"A nation of wolves will rise and a lion will soar," Netanyahu said.

-ABC News' Joe Simonetti

Defense Secretary Lloyd Austin spoke with Israeli Defense Minister Yoav Gallant on Sunday to reiterate U.S. support ahead of Monday’s Oct. 7 one-year anniversary.

Austin “reaffirmed U.S. support for Israel’s right to defend itself and noted that the United States maintains significant capability in the region to defend U.S. personnel and facilities, provide further support for Israel's self-defense and deter further escalation,” a readout provided by Pentagon Press Secretary Maj. Gen. Pat Ryder said.

The two “reiterated their commitment to deterring Iran and Iranian-backed partners and proxies from taking advantage of the situation or expanding the conflict,” the readout added.

Austin also “expressed his condolences” for two Israeli soldiers killed in a drone attack launched by Iran-aligned Iraqi militants on Oct. 3.

U.S. and Israeli officials are in close contact as the latter consider how to respond to Iran’s ballistic missile attack on Israel last week.

-ABC News’ Luis Martinez

The White House released a statement Monday to mark the first anniversary of the Oct. 7 attack, with President Joe Biden condemning "the unspeakable brutality" of the 2023 Hamas attack on southern Israel.

"One year later, Vice President [Kamala] Harris and I remain fully committed to the safety of the Jewish people, the security of Israel and its right to exist," Biden said.

"We support Israel's right to defend itself against attacks from Hezbollah, Hamas, the Houthis and Iran," the president added, noting the U.S. role in responding to Iran's most recent ballistic missile attack on Israel last week.

"We will never give up until we bring all of the remaining hostages home safely," the president said of the 101 captives still in Gaza.

Biden condemned the "vicious surge in anti-semitism in America and around the world," which he called "unacceptable."

For Palestinians, too, Biden said Oct. 7 should be remembered "as a dark day."

"Far too many civilians have suffered far too much during this year of conflict -- and tens of thousands have been killed, a human toll made far worse by terrorists hiding and operating among innocent people," he said.

"Israelis and Palestinians alike deserve to live in security, dignity, and peace. We also continue to believe that a diplomatic solution across the Israel-Lebanon border region is the only path to restore lasting calm and allow residents on both sides to return safely to their homes."

-ABC News' Lauren Minore

Hamas released a statement Sunday to mark the first anniversary of its Oct. 7 attack on southern Israel.

The statement attributed to leader Yahya Sinwar and deputy leader Khalil Al-Hayya described the attack as a “glorious” operation that “shattered the illusions the enemy had created for itself.”

The Hamas attack killed around 1,200 people in southern Israel and saw some 250 people taken to Gaza as hostages.

Monday’s statement said Hamas was ready “for an agreement that achieves the cessation of aggression, ends the siege and leads to a serious exchange deal,” accusing Israeli Prime Minister Benjamin Netanyahu of “procrastinating and obstructing” negotiations.

Hamas claimed responsibility for rocket fire that set off alarms in Tel Aviv and other parts of central Israel on Monday. One projectile landed south of Tel Aviv and wounded at least two people, emergency responders said.

The rockets were fired from the Khan Younis area of southern Gaza, the Israel Defense Forces said.

The Hamas-run Health Ministry in Gaza said 41,802 Palestinians have been killed in the strip since Oct. 7, 2023.

-ABC News’ Joe Simonetti, Matt Gutman and Sohel Uddin