The Israeli Army has told the UN that 1.1 million civilians living in the north of the Gaza Strip must move to the South within the next 24 hours, according to Reuters.
A UN spokesperson said the order is impossible to implement without devastating humanitarian consequences and has strongly appealled for "the cancellation of any such order, to avoid what could turn what is already a tragedy into a catastrophic situation".
The Israeli army's order also applies to all UN employees and those who reside in facilities affiliated with the organisation, including schools, health centres and clinics.
More than 300 Palestinians were killed on Thursday in Israel's attacks on the Gaza Strip, which continued for the sixth day. The total death toll since Saturday has risen to 1,537, with over 6,000 injured.
On the Israeli side, the number of deaths has reportedly risen to 1,300, with 3,300 casualties.
Israeli media reported that its military has targeted the Gaza Strip with 6,000 bombs, aimed at over 3,600 sites since last Saturday.
Palestinian President Mahmoud Abbas has condemned the violence against civilians.
Meanwhile, the World Health Organisation has warned the health system in the Gaza Strip is on the verge of collapse, due to the total Israeli blockade of power, water and food.
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