JERUSALEM (AP) — Israel has failed to meet U.S. demands to allow greater humanitarian access to the Gaza Strip, where conditions are worse than at any point in the 13-month-old war, international aid organizations said Tuesday.

United Nations officials described the situation in northern Gaza as “ apocalyptic ,” and warned the entire population there is at risk of death. The strikes come as a US’ deadline set last month for Israel to “surge” food and emergency aid into Gaza is set to expire. Aid groups said Israel has failed to meet the US demands.

An Israeli strike on a home in northern Gaza killed three siblings aged 6 and under, among at least six people killed in airstrikes in the war-ravaged territory, Palestinian medics said. In Lebanon, an Israeli airstrike on an apartment building south of Beirut on Wednesday killed at least six people and wounded 15, the Health Ministry said.