Washington — Vice President Kamala Harris is set to meet on Tuesday with families of hostages believed to be held by Hamas since the attack on Israel six months ago on Oct. 7.

Five Americans remain unaccounted for and are believed to have been taken hostage by Hamas during the attacks, after Israel announced last month that Itay Chen, a 19-year-old Israeli soldier with dual Israeli-U.S. nationality, was confirmed dead. The administration has made clear that it will continue to work for the release of all hostages and an immediate ceasefire between Israel and Hamas six months after the militant group's attack on southern Israel on Oct. 7. 

Harris is set to meet with families on Tuesday, after she did so in late October. The families of the hostages met with National Security Adviser Jake Sullivan on Monday. 

One of the family members, Rachel Goldberg-Polin, whose 23-year-old son Hersh is being held by Hamas in the Gaza Strip, said Sunday on "Face the Nation" before a meeting at the White House that it is a "failure" of global leaders and governments involved in hostage negotiations that her son and more than 130 others have been left in captivity for six months. 

"We are feeling extreme desperation, despair," she said. "And we've had wonderful access and sympathy, and open doors and lots of hugs from everyone in the U.S. government. But this is a very binary situation. We want our people back, period."

Israeli officials said that around 240 people were believed to have been taken hostage amid the Hamas terrorist attack on Oct. 7. Six months later, less than half of those captured have been returned. Parties gathered in Cairo over the weekend to restart negotiations to release the remaining hostages being held by Hamas.

U.S. and Qatari-led hostage diplomacy began in October, when two dual U.S.-Israeli hostages — a Chicago teenager and her mother — were released. Then, during a weeklong pause in fighting in November, more than 100 hostages were released, including two U.S. citizens, one of whom was only four years old. And in late December, the final American woman believed to be among the hostages, Judi Weinstein Haggai, was confirmed by Israel to have died.