The Qatari prime minister and other officials told the family members of six U.S. and Israeli hostages in Doha that this week's killing of senior Hamas official Saleh al-Arouri in Beirut has made efforts to secure a new deal much more difficult, according to a Qatari official and an Israeli source.

Why it matters: Saturday's meeting was the first time Qatari Prime Minister Mohammed bin Abdulrahman Al Thani has hosted families of Israeli hostages in Doha. His message illustrates just how complex any efforts to secure a new hostage deal have become as tensions rise across the region.

• It also signals how important this issue is for the Qatari prime minister and government, the Qatari official said.

State of play: Qatar and Egypt have been trying to relaunch indirect negotiations between Israel and Hamas over a new deal to secure the release of at least 40 hostages in return for several weeks of pause in the fighting in Gaza and the release of Palestinian prisoners.

• Nearly a week ago, Hamas gave Israel a new deal proposal, which also included a demand for Israel's withdrawal from Gaza. But Israel rejected it and the two sides remain far apart.
• On Tuesday, a strike in a southern Beirut suburb killed Hamas' Al-Arouri, causing Hezbollah to vow to retaliate. Israel hasn't publicly claimed or denied responsibility for the strike, but U.S. and Israeli sources previously confirmed Israel was behind the attack.

Behind the scenes: The families met with the Qatari prime minister on Sunday and told him the stories of their loved ones who are being held hostage in Gaza, according to the Qatari official and Israeli source.

• The Qatari prime minister told the group the current negotiations are very complex and briefed them on the challenges Doha is facing on both sides in its efforts to secure a new deal, the sources said.
• Those challenges now include the recent escalation of tensions after the assassination of al-Arouri earlier this week, the sources said. "The Prime Minister said it is more difficult to talk to Hamas after what happened in Beirut," the Qatari official told Axios.
• The Qatari prime minister told the family members that he was personally committed to continuing to try and secure a new hostage deal and that he was not going to give up regardless of the challenges, the Qatari official and the Israeli source said.

The family members also met Qatar's minister of state for foreign affairs, Mohammed bin Abdulaziz Al-Khulaifi, who is heading the Qatari negotiation team with Hamas and Israel.

• Al-Khulaifi was one of the architects of the previous agreement, which led to the release of more than 100 hostages.

What they're saying: "Qatar is painfully aware of the suffering of the remaining hostages and their loved ones," the Qatari official told Axios.

• "We have engaged directly with the hostages' families to share as much information as possible, and to assure them that Qatar is committed to using every resource to secure their release. We will continue to engage with these families," the official said.
• "We are using every possible channel, and collaborating closely with our counterparts in the U.S. and Israel…but Qatar is a mediator.  It does not control Hamas," the official stressed, adding that it's becoming "increasingly difficult" to preserve the channels of communication it has with Hamas due to the "escalation of bombardment in Gaza and elsewhere, which candidly complicates the hostage negotiations."
• "Clearly, there is more work to be done.  We are committed to continuing for as long as necessary," the official said.

The big picture: Since the Oct. 7 Hamas attack on Israel, Qatar has been under growing pressure from the U.S. Congress and Jewish American organizations over its relationship with the group, which is considered a terrorist organization by the U.S., Israel and several other countries.

• Republican Sen. Joni Ernst (Iowa) and Democratic Sen. Jacky Rosen (Nev.) sent a letter to President Biden last month asking him to put pressure on Qatar to strong-arm Hamas back to the negotiating table on a new hostage deal.
• Ernst visited Israel a few days ago with a congressional delegation and met with Prime Minister Benjamin Netanyahu and the Mossad director David Barnea and discussed the hostage negotiations.
• On Saturday, Ernst and the congressional delegation arrived in Doha and met with the Qatari prime minister.

What to watch: Senior U.S. and EU officials are in the region to try to de-escalate the rising tensions.

• The Lebanese militant group Hezbollah fired dozens of rockets toward Israel on Saturday in what it called its "initial response" to Arouri's killing. The Israeli military responded with strikes against what it said were Hezbollah targets.
• Secretary of State Tony Blinken is scheduled to visit both Israel and Qatar in the coming days. He is expected to discuss humanitarian conditions in Gaza, as well as the efforts to secure the release of the hostages, reduce regional tensions, and avoid escalation in Lebanon, the State Department said ahead of his trip.

Go deeper: Amid Gaza war, regional escalation draws U.S. deeper into Middle East crisis