Washington — White House national security adviser Jake Sullivan is set to meet Thursday with families of Americans taken hostage by Hamas, National Security Council spokesperson John Kirby said. 

CNN first reported the meeting, which comes after the families have previously met with Sullivan, according to the officials. Kirby said they expect all the families of those taken hostage to be at the meeting. 

President Biden had a virtual meeting with the families in October, and then met with families of hostages still held by Hamas last month.  That meeting came after a weeklong pause in fighting when more than 100 hostages were released, including two U.S. citizens, one of whom was only four years old. In late December, the final American woman believed to be among the hostages, Judi Weinstein Haggai, was confirmed by Israel to have died. 

The U.S. and Qatari-led Hostage diplomacy began in October with the release of two dual U.S.-Israeli hostages — a Chicago teenager and her mother. They were released in late October. 

The hostage diplomacy was led by Qatar, which negotiated with Hamas, and Egypt leant some assistance as well. Hamas wants Israel to stop the bombardment of Gaza. Israel is demanding the release of all hostages, including women of military age. 

The U.S. believes there are as many as six U.S. hostages remaining. 

Other senior members of the Biden administration, including Vice President Kamala Harris and second gentleman Doug Emhoff, have also met with the families. 

Around 240 people are believed to have been taken hostage amid the Hamas terrorist attack on Oct. 7, according to Israeli officials.  

Mr. Biden has pledged to work to bring the remaining American hostages home, saying in a statement marking 100 days of the Israel-Hamas war earlier this week that "we will never stop working to bring Americans home."

"I look forward to maintaining close contact with my counterparts in Qatar, Egypt, and Israel to return all hostages home and back to their families," he said. 

Senate Majority Leader Chuck Schumer and a bipartisan group of senators held a press conference with some family members of Americans being held hostage on Wednesday. Schumer said they were making "important progress" although he admitted it was "slow, slow, slow."  

"So we are going to do everything," Schumer said. "We can, we are going to do everything we can because our hearts are broken and we must, we must bring them home. All of them. I just want to say to, to all of you, don't give up hope."

Jon Polin, whose son was taken hostage at a music festival targeted in the Oct. 7 attack, applauded the U.S. government's efforts to date, but he urged more action.

"As Americans, we expect the United States — the greatest superpower in the history of the world — to use its full power to secure the hostages' release," he said. 

The FBI and State Department, along with the White House, have continued to consult with the Israeli government on the hostages and efforts to broker their release. The Netanyahu government has faced widespread protests in Israel by families of hostages who want the release of their loved ones prioritized amid the focus on the warfighting. 

On Friday, Sullivan's hostage diplomacy efforts will continue. He will meet with Anna Corbett, whose husband Ryan Corbett, a U.S. citizen, has been held by the Taliban since 2022 and is considered by the State Department to be wrongfully detained. The U.S. does not recognize the Al Qaeda-linked Taliban as a legitimate government in Afghanistan.

In:
• Hamas
• Israel
• White House

Margaret Brennan

Margaret Brennan is moderator of CBS News' "Face The Nation" and CBS News' senior foreign affairs correspondent based in Washington, D.C.