A prominent Jewish MP has compared the actions of Israeli troops with Nazis who forced his family to flee Poland.
Sir Gerald Kaufman, MP for Gorton in Manchester, drew the parallel during a Commons debate on the Gaza conflict.
Some members of the Jewish community - including his fellow MPs - have questioned the comments.
Louise Ellman MP, of the Labour Friends of Israel group, said the "dreadful" war in Gaza was not comparable to German actions in World War II.
Sir Gerald, who was brought up as an orthodox Jew and Zionist, told MPs: "My grandmother was ill in bed when the Nazis came to her home town .. a German soldier shot her dead in her bed. "My grandmother did not die to provide cover for Israeli soldiers murdering Palestinian grandmothers in Gaza."
"The present Israeli government ruthlessly and cynically exploit the continuing guilt from gentiles over the slaughter of Jews in the Holocaust as justification for their murder of Palestinians. "
Palestinian deaths in the Gaza Strip have passed 1,000, medical sources in Gaza say, but Israel has continued to resist international calls for a ceasefire.
The Israeli government says the action is necessary to prevent Hamas rocket attacks into southern Israel.
Labour MP Louise Ellman said: "The Nazis were about rounding up and exterminating people because of their origins.
"What we're witnessing in Gaza is a dreadful war and the Israelis are trying to stop Hamas continuing to launch rockets from Gaza, targeting and killing and murdering Israeli citizens."
But speaking to the BBC on Friday, Sir Gerald said he was standing by his comments.
"We had an IRA bomb in Manchester which destroyed much of the centre - we didn't send troops over to Belfast to murder 1,000 Catholics."
Sir Gerald said he had been a long-term supporter of Israel and has personally known many of its prime pinisters.
But he added: "I am not going to stand by and keep silent when the Israeli troops - with a dreadful government sending them there - kill large numbers of innocent people with no useful result at the end of it all."