WASHINGTON

US President Joe Biden and Vice President Kamala Harris, the Democratic nominee to succeed him, were briefed by their national security team Wednesday on the situation in the Middle East.

The briefing comes ahead of closely-watched negotiations in Doha, Qatar that are slated to begin Thursday on efforts to bring a cease-fire to the besieged Gaza Strip.

The critical talks are about to transpire as the region braces for a potential retaliatory strike from Iran after the Palestinian group Hamas's political leader, Ismail Haniyeh, was assassinated in the Iranian capital Tehran last month. Iran and its regional allies have placed blame squarely on Israel for the killing, though Tel Aviv has not confirmed or denied responsibility.

The White House said Biden and Harris "were updated on US military efforts to support the defense of Israel."

"They were also briefed on continued diplomatic efforts to de-escalate regional tension and to bring the cease-fire and hostage release deal to a conclusion," it added.

The White House earlier Wednesday said Biden is dispatching CIA Director Bill Burns and Brett McGurk, the president's senior official for the Middle East, to represent the US at the talks.

Hamas said earlier in the day that it will not join the latest round of negotiations. On Sunday, Hamas demanded that Gaza cease-fire mediators present a plan to implement a proposal supported by Biden, which it agreed with on July 2.

The decision came after Egyptian, Qatari and US mediators urged Israel and Hamas last week to conclude a cease-fire and hostage release deal with no further delays or excuses.

Biden said in May that Israel presented a three-phase deal that would end hostilities in Gaza and secure the release of hostages held in the coastal enclave. The plan includes a cease-fire, a hostage-prisoner exchange and the reconstruction of Gaza.

Indirect talks mediated by the US, Qatar and Egypt have failed to agree on specific terms because Israeli Prime Minister Benjamin Netanyahu has refused to accept Hamas’s demand to end the onslaught in Gaza.

Nearly 40,000 Palestinians have been killed during Israel's war in Gaza, the vast majority of whom have been women and children. Vast tracts of the coastal territory have been completely leveled amid an relentless Israeli bombardment that has left entire neighborhoods reduced to rubble.

Gazans continue to face acute shortages of food, water and medicine due to Israeli restrictions on the entry of humanitarian assistance, as well as the significant curtailment of movement for aid convoys once they enter the Strip.

A total of 1,139 people were killed in the cross-border attack led by Hamas on Oct. 7, which precipitated the current war.