An Israeli airstrike on a school sheltering displaced families in northern Gaza killed at least 23 people, while another hit a children's hospital, local health officials said.

France, Germany and Britain meanwhile said Israel's seven-week blockade on all imports to Gaza was "intolerable."

An Israeli airstrike on a school sheltering displaced families in northern Gaza killed at least 10 people, while another hit a children's hospital, local health authorities said, taking Wednesday's death toll to 20.