WASHINGTON — President Biden said Wednesday that the terrorist group Hamas has agreed to allow some US citizens to leave the Gaza Strip, as the Israeli military invades and heavily bombs the Palestinian territory.

The White House wouldn’t say how many US citizens are being allowed to leave. Secretary of State Antony Blinken said Tuesday that approximately 400 American individuals and families are “stuck” there.

“Today, thanks to American leadership, we secured safe passage for wounded Palestinians and for foreign nationals to exit Gaza,” Biden tweeted as he traveled to Minnesota for an unrelated day trip.

“We expect American citizens to exit today, and we expect to see more depart over the coming days,” Biden wrote. “We won’t let up working to get Americans out of Gaza.”

At an address on economic policy, Biden said that “American citizens are able to exit today as part of the first group of probably over 1,000. We’ll see more of this process going on in the coming days.”

“We’ve all seen the devastating images from Gaza,” he added. “Palestinian children crying out for lost parents, parents writing their children’s names on their hands and legs to be identified if the worst happens.”

National Security Council spokesman John Kirby called the development a “significant breakthrough” but declined to provide specific details during a gaggle with reporters on Air Force One.

“I won’t go beyond saying a handful of Americans, that’s as specific as I’m gonna get today,” Kirby said.

“This is a significant breakthrough. It certainly was a focus of the president’s calls with [Egyptian] President [Abdel Fattah el-]Sisi and [Israeli] Prime Minister [Benjamin] Netanyahu on Sunday, where this arrangement was discussed in detail.”

Kirby added, “A handful of Americans are expected to depart today and we expect to get more to come in future days. The State Department has communicated directly with American citizens and Gaza over the past 24 hours to tell them to be ready to go and to await further instruction.”

Blinken said Tuesday during congressional testimony that there were roughly 400 Americans stranded in Gaza, plus 600 immediate family members.

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“We have about 400 American citizens and their family members, so it’s roughly 1,000 people who are stuck in Gaza and want to get out. I’m focused on this intensely,” Blinken told the Senate Committee on Appropriations.

There also are up to 10 US citizens who were kidnapped by Hamas terrorists and taken to Gaza during the jihadists’ Oct. 7 surprise attack on southern Israel, in which at least 33 Americans were among the more than 1,400 slaughtered in communities near Gaza.

Hamas released two kidnapped US citizens on Oct. 20 and US officials have been coy about exactly how many are believed to remain captive.