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Norwegian Foreign Minister Anniken Huitfeldt condemned Israel's siege of Gaza in retaliation to the Hamas group attacks as Europe reacted to an overnight order for a million Palestinians to evacuate their homes.
"Israel is entitled to defend itself ... but it cannot use all possible means," Ms Huitfeldt said on Friday. "I condemn this siege because you have to, when they ask so many people to leave, when they don't have access to food and medicine."
Ireland's Deputy Prime Minister called on Israel to rescind the order for Gaza residents to leave their homes in the northern areas enmasse, saying "two wrongs don't make a right".
"It simply isn't feasible that a million people can move out of the city in 24 hours," Micheal Martin, who is also Foreign Minister in the coalition government.
"That call by Israel should be rescinded and should be pulled back because I think everybody knows it's not something that can be achieved at all and I think it puts enormous trauma on the ordinary civilians and Gazans.
"Two wrongs don't make a right and there's an obligation to protect civilians in Gaza, to protect children and families and so forth and people who have nothing to do with Hamas."
Britain's Foreign and Commonwealth Office updated the country's travel advice for its citizens on Friday as it urged anyone affected to obey the Israeli military orders.
"We advise following this advice issued by the Israeli authorities," it said. "We recognise this is a fast-moving situation that poses significant risks."
Rishi Sunak, the British prime minister, leads a government that has taken a line that puts less pressure on Israel. Speaking at a summit of northern European leaders, he said the plight of civilians must always be paramount. “It is something I’ve discussed with Prime Minister Netanyahu myself and underlined with what the secretary of state from the United States and the president have said, that of course Israel should take every possible precaution to protect civilians as they exercise their rightful ability to defend themselves against attacks like this.”
Speaking to Radio 4’s Today programme on Friday, Mr Shapps said the operation must stay within the bounds of international law in its operation to root out Hamas militants.
“It is the case that we want to enable Hamas to be removed from the scene but to do so in a manner that does not affect the Palestinian population, as far as is possible.
“And the difficulty is that Hamas hide themselves within that population deliberately, with a deliberate policy of using the population as human shields.
“So, Israel is letting people know in advance, and we very much support advance notice being given.”
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Mr Shapps said "it seems very likely" that there are British hostages in Gaza.
"We don't have exact data on that, for obvious reasons. But within Gaza there will also be Brits or possibly people with dual nationalities as well. The Prime Minister has spoken to the Egyptian President about using that border to get people out," he said.
"I can't go into specific detail. What I can tell you is it is highly likely, no one will know for sure, that there are those – either British nationals or people with joint nationality – involved in the hostage situation, as has been reported previously.
"And secondly, that we're sending assistance and expertise, including intelligence, to the region, and to a number of different locations.
"But this is not the same as saying we're sending people into Gaza itself."