Sen. Lindsey Graham, R-S.C., said he is "heartbroken, devastated, mad" over the six hostages whose bodies were recovered Saturday in Gaza.
The hostages, which included 23-year-old Israeli American Hersh Goldberg-Polin, "were brutally murdered by Hamas terrorists shortly before we reached them," Israel Defense Forces spokesperson Rear Adm. Daniel Hagari said. IDF officials identified the additional five hostages as Carmel Gat, Eden Yerushalmi, Alexander Lobanov, Almog Sarusi and Master Sgt. Ori Danino.
"If you want the hostages home, which we all do, you have to increase the cost to Iran. Iran is the great Satan. Hamas is the junior partner. They're barbaric, religious Nazis -- Hamas, they could care less about the Palestinian people," Graham told "This Week" co-anchor Jonathan Karl during an interview on Sunday. "I would urge the Biden administration and Israel to hold Iran accountable for the fate of [the] remaining hostages and put on the target list oil refineries in Iran if the hostages are not released."
Graham urged President Joe Biden and Israeli Prime Minister Benjamin Netanyahu to "tell the Ayatollah [Ali Khamenei] what he values is on the target list. Until that happens, nobody is coming home."
MORE: Biden administration throws cold water on prospect of renewed Iran nuclear talksGraham, one of former President Donald Trump's closest allies on Capitol Hill, also criticized Vice President Kamala Harris for not attending Netanyahu's speech to a joint session of Congress in July, saying: "She boycotted Bibi's speech to Congress, sending a signal to Hamas and Iran that America does not really have Israel's back."
At the time, a Harris aide insisted to ABC News that the vice president did not preside because of a scheduling conflict, not to boycott or snub the Israeli prime minister. When pressed by Karl on Sunday that Republican vice presidential candidate JD Vance also decided to not attend the address, Graham defended the Ohio senator, saying: "JD has been unequivocally supporting Israel. She [Harris] has been horrible. She is slow-walking weapons. She did not attend the speech, and that juiced up every terrorist in the region."
"I would say on foreign policy, she [Harris] has been a wrecking ball," Graham said.
Graham said Trump should highlight her failure on foreign policy and her role with the southern U.S. border at the ABC News presidential debate scheduled for Sept. 10.
While he acknowledged Harris "obviously has some talent" given her political experience, Graham said overall "her job performance has been lousy" as vice president. He urged Trump to focus on issues in a head-to-head race, saying: "Every poll says the same thing. The American people trust you with what matters the most to them -- the economy, inflation, border security and just managing the government."
"If I were you, my friend, I would focus on those issues laser-like and you will win this race," he added.
MORE: Trump adds new campaign pledge to get IVF paid for by government or covered by insuranceTrump last week added a new campaign pledge to get IVF paid for by the government or covered by insurance. When asked Sunday about Trump's IVF announcement, Graham told Karl: "I think he [Trump] just tried to show his support for IVF treatments that, you know, we've been accused, the party has, of being against birth control. We are not. We've been accused of being against IVF treatments. We're not."
Graham said he'd support a tax credit for Americans using IVF and other treatments to become pregnant.
"I would support a tax credit," Graham said. "That makes sense to me, to encourage people to have children."
However, when pressed by Karl, the South Carolina senator said he does not support mandating insurance companies to cover what Trump proposed regarding IVF.
"You wouldn't support this idea of mandating insurance companies to cover this, would you?" Karl asked.
"No. No, I wouldn't because there's no end to that," he said. "I think a tax credit for children makes sense, means tested. ... I'll talk to my Democratic colleagues. We might be able to find common ground here."
The presidential debate set to be held by ABC News will take place at the National Constitution Center in Philadelphia on Sept. 10 and will be moderated by "World News Tonight" anchor and managing editor David Muir and ABC News Live "Prime" anchor Linsey Davis. It will be produced in conjunction with ABC station WPVI-TV/6abc, and will air live at 9 p.m. ET on the network and on the ABC News Live 24/7 streaming network, Disney+, and Hulu.