Civilian safe passage from Ukraine's besieged eastern port city of Mariupol was "halted" on Sunday for a second consecutive day, the International Committee of the Red Cross said.
"Amid devastating scenes of human suffering in Mariupol, a second attempt today to start evacuating an estimated 200,000 people out of the city came to a halt," the ICRC said.
"The failed attempts yesterday and today underscore the absence of a detailed and functioning agreement between the parties to the conflict," it added.
"The ICRC is not and cannot in any way be the guarantor of a ceasefire agreement between the parties or of its implementation," the body added, criticising the lack of a proper agreement between the warring parties to protect civilian lives amid ceasefire violations.
"For the safe passage of civilians to happen with the required levels of trust, the parties should agree between themselves not just in principle but also on the details and parameters" of an evacuation accord, the ICRC added, stressing its neutrality.
"In addition, the ICRC needs satisfactory security guarantees in order to operate. Today, our teams began opening up the evacuation route from Mariupol before hostilities resumed," the humanitarian organisation said.
It underlined its readiness "to help facilitate further attempts if the parties reach a detailed agreement, which is for the parties alone to implement and respect".
The organisation reminded both sides that staff, vehicles and buildings bearing Red Cross emblems are protected under international law as it urged them "to respect international humanitarian law and to protect civilians and civilian infrastructure".
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