Evacuating these areas would require time, they say, and there could be huge numbers of casualties. It's an ominous sign of Israel's threat to significantly expand its military campaign in Gaza. The former Israeli prime minister, Ehud Olmert, has been one of very few senior Israelis so far to speak out against expanding the military campaign in Gaza. In an interview with the BBC, Olmert said: "Most Israelis are against what is happening, large numbers of the [army's] commanders are against expanding the military operation and want to end the war right now." Olmert is a frequent and increasingly vocal critic of Israel's current Prime Minister Benjamin Netanyahu, and his views reflect growing concern about the impact of the 20-month-long war on the country's morale, economy and international standing. Olmert was also outspoken on the humanitarian impact of the war on the residents of Gaza. "It's totally intolerable, unacceptable and unforgivable, it needs to be stopped right away," said the former top official, who has been accused by pro-government outlets of "lobbying for Palestinians". He added: "We have to provide all of the humanitarian needs of the population. We can't allow morally the beginning of famine in Gaza. That has to stop." Such opinions are rarely reflected in the Israeli media or in public opinion polls but they've been urgently repeated in passionate speeches in recent days by UN organisations, aid agencies and by some of Israel's allies abroad – French President Emmanuel Macron called Israel's actions in Gaza "shameful". Netanyahu accused him of "standing with Hamas". There's growing evidence of profound suffering across Gaza after a 10-week blockade, during which Israel has prevented the entry of any food, medicines or fuel into the Palestinian enclave. A UN-backed assessment has said that Gaza's population of around 2.1 million Palestinians is at "critical risk" of famine and faces "extreme levels of food insecurity". The World Health Organisation says without enough nutritious food, clean water and access to health care, an entire generation will be permanently affected. Israeli government spokesman David Mencer insisted to the BBC that "Israel is certainly not starving Gaza". "I don't dispute that there is hunger in Gaza, but we believe that it is hunger caused by Hamas. There is food in Gaza, that's our information. There is no famine," he said. Israel also resumed its aerial bombardment of Gaza on 18 March and its attacks have killed 2,799 since then, according to the territory's Hamas-run health ministry, including 80 people on Wednesday.