WASHINGTON — President Biden announced Tuesday that Hamas is holding Americans hostage in Gaza and that at least 14 US citizens are confirmed to have died in the terrorist group’s weekend rampage across southern Israel.

“We now know that American citizens are among those being held by Hamas,” Biden said at the White House during remarks in which he likened Hamas to ISIS and blasted them as “sheer evil.”

Biden didn’t say how many Americans are among the roughly 150 people believed to have been abducted and White House national security adviser Jake Sullivan said moments later that the number remains murky.

The hostages were taken to Gaza, which Hamas has ruled since 2007, during a series of Saturday morning raids by air, land and sea — in which jihadists also slaughtered more than 1,000 civilians and Israeli troops.

“I’ve directed my team to share intelligence and deploy additional experts from across the United States government to consult with and advise Israeli counterparts on hostage recovery and recovery efforts because as president, I have no higher priority than the safety of Americans being held hostage around the world,” Biden said.

The 80-year-old president gave the roughly 10-minute speech after remaining out of public view on Monday and Sunday. He took no questions from the press. Biden previously addressed the crisis in a three-minute speech on Saturday afternoon, before the full scale of the carnage became clear.

Biden did not address calls from Republican politicians to halt the release of $6 billion in unfrozen assets to Iran, which reportedly helped Hamas plot the attacks and gave the go-ahead for the assault last week.

He also didn’t directly mention pro-Hamas protests in major US cities or the handful of congressional Democrats who slammed Israel after the attacks, though press secretary Karine Jean-Pierre later Tuesday denounced what she called “repugnant” comments from those legislators — without mentioning names.

“There are moments in this life, and I mean this literally, when pure, unadulterated evil is unleashed on this world. The people of Israel lived through one such moment this weekend,” Biden began his statement, flanked by Vice President Kamala Harris and Secretary of State Antony Blinken.

“This was an act of sheer evil. More than 1,000 civilians slaughtered — not just killed, slaughtered — in Israel. Among them, at least 14 American citizens killed.”

The president detailed: “Parents butchered using their bodies to try to protect their children. Stomach-turning reports of babies being killed. Entire families slain. Young people massacred while attending a musical festival to celebrate peace — to celebrate peace. Women raped, assaulted, paraded as trophies. Families hidden in fear for hours and hours, desperately trying to keep their children quiet to avoid drawing attention.

“There’s still so many families desperately waiting to hear the fate of their loved ones, not knowing if they’re alive or dead, or hostages,” Biden went on.

“Infants in their mothers’ arms, grandparents in wheelchairs, Holocaust survivors abducted and held hostage — hostages who Hamas has now threatened to execute in violation of every code of human morality. It’s abhorrent.”

The president added that “the brutality of Hamas … brings to mind the worst rampages of ISIS.”

Biden and Harris spoke on the phone with Israeli Prime Minister Benjamin Netanyahu on Tuesday morning, the third call between the two men since the attacks.

The president said he told Netanyahu he expected Israel to come down hard on Hamas and that the US government would help supply the weapons.

“I told him, if the United States experienced what Israel is experiencing, our response would be swift, decisive and overwhelming,” Biden said.

Israel-Hamas war: How we got here

2005: Israel unilaterally withdraws from the Gaza Strip more than three decades after winning the territory from Egypt in the Six-Day War.

2006: Terrorist group Hamas wins a Palestinian legislative election.

2007: Hamas seizes control of Gaza in a civil war.

2008: Israel launches military offensive against Gaza after Palestinian terrorists fired rockets into the town of Sderot.

2023: Hamas launches the biggest attack on Israel in 50 years, in an early-morning ambush Oct. 7, firing thousands of rockets and sending dozens of militants into Israeli towns.

Terrorists killed more than 1,200 Israelis, wounded more than 4,200, and took at least 200 hostage.

Israeli Prime Minister Benjamin Netanyahu was quick to announce, “We are at war,” and vowed Hamas would pay “a price it has never known.”

The Gaza Health Ministry — which is controlled by Hamas — reported at least 3,000 Palestinians have been killed and more than 12,500 injured since the war began.

“We’re surging additional military assistance, including ammunition and interceptors to replenish Iron Dome. We’re gonna make sure that Israel does not run out of these critical assets to defend its cities and its citizens.”

“In this moment, we must be crystal clear. We stand with Israel. We stand with Israel,” Biden said.

“And we will make sure Israel has what it needs to take care of its citizens, defend itself and respond to this attack.”

Biden left his subordinates to answer reporter questions on the crisis — with Sullivan saying Tuesday afternoon later that many answers remained elusive.

“We do not know the number of hostages we have at this time,” he told reporters at the daily White House briefing. 

“We believe that there are 20 or more Americans who at this point are missing, but I want to underscore and stress that does not mean necessarily that there are 20 or more American hostages.”

Sullivan also insisted the US has not confirmed that Iran helped plot the rampage.

The Wall Street Journal reported that Tehran helped plan the incursion and gave a final signoff last Monday at a meeting in Beirut.  The Journal cited senior officials in Hamas and the Lebanese militant group Hezbollah and reported that Syrian and European sources also confirmed Iran’s role.

“Iran is complicit in this attack in a broad sense because they have provided the lion’s share of the funding for the military wing of Hamas,” Sullivan said at the White House briefing.

“They provided training, they have provided capabilities, they have provided support and they have had engagement and contact with Hamas over years and years — and all of that has played a role in contributing to what we have seen. Now, as to the question of whether Iran knew about this attack in advance or help plan or direct this attack, we do not — as of the moment I’m standing here at the podium — have confirmation of that.”

Sullivan also deflected on whether the US would attempt to halt the disbursement of $6 billion that Biden authorized in August for Iran’s government to use on humanitarian goods, in exchange for the release of five US citizens. The money is being administered by Qatar, which is friendly to both Hamas and the US.

“We have not yet had one dollar of that $6 billion spent and I will leave it at that,” Sullivan said.

Jean-Pierre, meanwhile, gave an uncharacteristically strong denunciation of fellow Democrats who in recent days focused on alleged Israeli government mistreatment of Palestinians in the wake of the attacks. Reps. Cori Bush (D-Mo.), Rashida Tlaib (D-Mich.), Alexandria Ocasio-Cortez (D-NY) and Ilhan Omar (D-Minn.) issued statements slamming Israeli actions, with Ocasio-Cortez demanding an “immediate ceasefire.”

“We believe they’re wrong, we believe they’re repugnant and we believe they’re disgraceful,” Jean-Pierre said of the president’s fellow Democrats. “There are not two sides here.”