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The leaders of the bloc's 27 nations expressed in a declaration the "gravest concern for the deteriorating humanitarian situation in Gaza".
They called for "continued, rapid, safe and unhindered humanitarian access and aid to reach those in need through all necessary measures, including humanitarian corridors and pauses for humanitarian needs".
In their declaration, the leaders repeated their previous condemnation "in the strongest possible terms" of the Hamas attack and emphasised Israel's right to defend itself "in line with international law and international humanitarian law".
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They also repeated a call for Hamas to immediately release all hostages "without any precondition".
"The European Union will work closely with partners in the region to protect civilians, provide assistance and facilitate access to food, water, medical care, fuel and shelter, ensuring that such assistance is not abused by terrorist organisations," the declaration said.