Sex And The City actress Cynthia Nixon is among activists who have begun a hunger strike to demand US President Joe Biden calls for a permanent ceasefire in the Israel-Hamas war.
Politicians from five US states are also taking part in the action that began on Monday.
Nixon, who formerly ran for mayor of New York City, told a crowd outside the White House her two children are Jewish and their grandparents are Holocaust survivors.
She said: “I have been asked by my son to use any voice I have to affirm as loudly as possible that never again means never again for everyone.
“In seven weeks Israel has killed more civilians on a tiny strip of land than was killed in 20 years of war in the entire country of Afghanistan.
“I am sick and tired of people explaining away by saying that civilian casualties are a routine toll of war. There is nothing routine about these figures. There is nothing routine about these deaths.
“I would like to make a personal plea to a president who has, himself, experienced such devastating personal loss, to connect with that empathy for which he is so well known and to look at the children of Gaza and imagine that they were his children.”
The five politicians taking part in the action are Delaware state representative Madinah Wilson-Anton, New York representative Zohran Mamdani, Oklahoma representative Mauree Turner, Virginia representative Sam Rasoul and Michigan representative Abraham Aiyash.
Mr Mamdani and Ms Wilson-Anton are reportedly among a small group of activists who will be on hunger strike for five days.
Nixon has said she will end hers on Tuesday to return to New York for work commitments.
The hunger strike was launched to coincide with what had been the scheduled end of a four-day truce in the Israel-Hamas conflict.
Israel has so far released 117 of 150 Palestinian prisoners it said it would free as part of the agreement, while Hamas has released 51 Israeli hostages during the pause in fighting.