US President Joe Biden warned Tuesday of a "very, very dangerous" situation if Israel and Hamas fail to reach a Gaza ceasefire by the Muslim holy month of Ramadan.
Biden added that it was up to Hamas whether to accept an offer for a six-week truce, while warning Israel there were "no excuses" for failing to allow aid into the Palestinian territory.
"It's in the hands of Hamas right now," the 81-year-old Biden told reporters as he prepared to fly back to the White House from the Camp David presidential retreat in Maryland.
"The Israelis have been cooperating, the offer (of a ceasefire) is rational. We'll know in a couple of days. But we need the ceasefire."
He added: "There's got to be a ceasefire because Ramadan -- if we get into circumstances where this continues to Ramadan, Israel and Jerusalem could be very, very dangerous."
Ramadan will start on March 10 or 11, depending on the lunar calendar.
Biden did not elaborate, but the United States last week urged Israel to allow Muslims to worship at the flashpoint Al-Aqsa mosque compound in Jerusalem during Ramadan, after a far-right minister proposed barring Palestinians from the occupied West Bank.
The US president, who last week ordered the United States to start airdropping humanitarian relief into the besieged territory of 2.4 million people, also said he was pushing Israel to let more aid in.
"I'm working with them very hard," he said. "We must get more aid into Gaza. There's no excuses, none."
Biden also brushed off suggestions of tensions with Prime Minister Benjamin Netanyahu as Washington presses Israel over civilian deaths, and after one of Netanyahu's rivals in the Israeli war cabinet visited the White House on Monday.
He said their relationship was "like it's always been."
Democrat Biden and rightwinger Netanyahu have often been at odds during the four decades in which their political paths have crossed, but Biden has stuck steadfastly by Israel during its war with Hamas.
The war started with Hamas's October 7 attack on southern Israel that resulted in about 1,160 deaths, most of them civilians, according to an AFP tally based on Israeli official figures.
Israel's retaliatory offensive has killed 30,631 people, mostly women and children, according to the health ministry.
