US Secretary of State Antony Blinken heads back to the Middle East on Thursday on his fourth trip since Israel's war on Gaza, to press for immediate new aid for battered Gaza and de-escalation in the region.
The top US diplomat will visit both Israel and the occupied West Bank, home of the Palestinian Authority, and five Arab countries - Egypt, Jordan, Qatar, Saudi Arabia and the United Arab Emirates, the State Department said.
Blinken will leave late Thursday and first go to Turkey - that has increased its criticism on ongoing Israeli aggression on Gaza- followed by Greece.
Blinken will discuss "immediate measures to increase substantially humanitarian assistance to Gaza," where the World Health Organisation has warned of the risk of famine and disease.
"We don't expect every conversation on this trip to be easy. There are obviously tough issues facing the region and difficult choices ahead," State Department spokesman Matthew Miller told reporters.
"But the secretary believes it is the responsibility of the United States of America to lead diplomatic efforts to tackle those challenges head on," he said.
Blinken on previous trips sought to keep the war isolated to Gaza. But he returns to a region that has seen attacks in or from Lebanon, Iraq, Yemen, Syria and Iran.
Israel on Tuesday carried out a strike inside Lebanon that killed a top Hamas leader, and Yemen-based Houthi rebels have been firing on ships in the Red Sea in avowed solidarity with Gaza.
In a pre-trip telephone call, Blinken agreed with French Foreign Minister Catherine Colonna to "de-escalate tensions in the West Bank and to avoid escalation in Lebanon and Iran," the State Department said.
Iran was hit Wednesday by the deadliest attack since its 1979 Islamic revolution, which killed at least 84 people, although the Islamic State group claimed responsibility and US officials rejected any US or Israeli role.
President Joe Biden's administration has provided support for Israel since the Hamas attack on October 7, that led to the killing of around 1,140 people - according to Israeli figures.
The United States has twice exercised its veto at the UN Security Council against ceasefire calls, drawing outrage in the Arab world, and just days ago Blinken for the second time bypassed Congress to rush weapons to Israel.
But Biden has also openly voiced exasperation at Prime Minister Benjamin Netanyahu as he pursues a relentless military offensive in the Gaza Strip, much of which has been reduced to rubble.
More than 22,400 people in the Gaza Strip have died, mostly civilians, according to the Palestinian health ministry in the enclave, and the vast majority of residents of the impoverished and blockaded territory have been forced from their homes.
The Biden administration has taken credit for coaxing Israel on several aid issues including allowing limited gas and commercial trucks to enter.
Another concern for the Biden administration has been calls by far-right members of Netanyahu's cabinet for the mass expulsion of Palestinians from the Gaza Strip.
Blinken is also likely to press Israel to stop blocking the transfer of tax revenue to the Palestinian Authority, a longstanding arrangement that is opposed by Israel's far-right finance minister, Bezalel Smotrich.
The United States sees a future in the Gaza Strip for the Palestinian Authority, whose ruling Fatah faction is the rival of Hamas, but Netanyahu has long sought to weaken the semi-autonomous body and opposes the eventual creation of a Palestinian state.
Blinken will also pay a brief visit Saturday to Greece, which is jittery about an expected US sale of advanced F-16 fighter-jets to Turkey, its historic adversary.
The Biden administration is expected to offer the jets once Turkey gives a long-delayed greenlight to NATO membership for Sweden, which shed earlier hesitation on entering the Western military alliance following Russia's invasion of Ukraine.
NATO requires unanimity and Turkish President Recep Tayyip Erdogan had used his leverage to press for concessions, including action by Sweden against Kurdish militants opposed to Ankara.
Turkey's parliament is moving ahead on ratification. Turkey last year allowed the entry into NATO of Finland, which had launched a joint membership bid with Sweden.