US Secretary of State Antony Blinken was headed to the Middle East on Monday to push forward a ceasefire plan, but Israeli politics and Hamas’ silence raised further questions about whether he will be able to succeed.

This is his eighth visit to the region since the war broke out. The top US diplomat will begin his trip from Egypt and will travel to Israel later on Monday.

Blinken will first hold closed-door talks in Cairo with President Abdel Fattah al-Sisi, a key US partner in peace efforts, and later with Prime Minister Benjamin Netanyahu in Jerusalem.

Blinken planned the trip to advance a proposal announced May 31 by President Joe Biden, who has pushed efforts to end a war that has taken a growing toll on civilians and alienated parts of his base ahead of the November election.

But Hamas, which launched the war with a massive attack on Israel on October 7 followed by a sustained retaliation, has not formally responded.

And while Biden has described his plan as coming from Israel, the resignation on Sunday of Benny Gantz, a key centrist, from Netanyahu’s war cabinet has cast a new shadow over U.S. diplomatic efforts.

Gantz, a former general who is leading in opinion polls to replace Netanyahu if new elections are held, protested that the prime minister has not taken tough decisions to achieve “real victories,” including considering a post-war plan for Gaza.

Gantz has presented himself as a smoother partner for the United States than Netanyahu, a veteran of political feuds with Israel’s key ally. Biden in recent weeks suspended arms shipments to Israel and accused Netanyahu of prolonging the war to stay in power, a claim he has backed down from.

Gantz challenged Netanyahu by visiting Washington alone in March and has regularly met with Blinken in Israel, though a meeting on the latest trip was not immediately announced.

The Dilemma of Crossing the Border

The short-term effect of Gantz’s exclusion from the war cabinet could be that it will eliminate a counterbalance to Netanyahu’s right-wing allies, who hate any compromise and have threatened to leave the cabinet if Israel accepts the ceasefire plan.

Israel also showed on Saturday that it has tools beyond diplomacy to free hostages – its top priority – in an operation that freed four Israeli hostages and killed 274 others, according to Palestinian officials.

Overall, at least 37,084 people, mostly civilians, have been killed in Gaza in Israel’s retaliatory military offensive, according to the regional health ministry.

Hamas attacks on southern Israel on October 7 killed 1,194 people, mostly civilians, according to an AFP count based on Israeli official figures.

According to the plan laid out by Biden, Israel will withdraw from Gaza populated centers and Hamas will free hostages. The ceasefire will initially last for six weeks, with the truce to be extended until negotiators seek a permanent end to hostilities.

Biden’s national security adviser, Jake Sullivan, said on Sunday that it was hard to say what impact the rescue operation would have on the ceasefire talks.

“If Hamas said yes to negotiations, the need for these types of operations would end because the hostages would be released peacefully, not through military action,” Sullivan told ABC News.

In Egypt, Blinken is also expected to talk to Sisi about a solution to opening the key crossing into Gaza at Rafah.

The months-long blockade has worsened the humanitarian disaster in Gaza, sending prices of scarce commodities soaring and raising United Nations fears of famine in the blockaded territory.

Israel has recaptured the crossing from Hamas and blamed Egypt for the incident.

Egypt, the first Arab state to make peace with Israel, has hit back, saying drivers feel unsafe passing through what is now an Israeli checkpoint.

Blinken was heading to the region from France, where he accompanied Biden on a state visit that marked the 80th anniversary of the D-Day landings of Allied forces in German-occupied Normandy.

Blinken will also visit two more key Arab partners, Jordan and Qatar, before returning to Italy on Wednesday to join Biden at the Group of Seven summit.