The International Committee of the Red Cross (ICRC) announced on Sunday that a second attempt to evacuate residents of Mariupol, a strategic port in southeastern Ukraine surrounded by Russian forces and their allies, has been “stalled”.

An earlier attempt to evacuate civilians from this city of about 450,000 people, which the Russians and their allies bombed for days from the breakaway regions of Donbass, failed on Saturday, with both sides accusing each other of not honoring their obligations.

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“Amid horrific scenes of human suffering in Mariupol, today a second attempt to start evacuating some 200,000 people from the city has been halted,” the International Committee of the Red Cross said in a statement.

The ICRC is asking the two parties to agree on “special terms” for evacuation agreements.

The Ukrainians claimed that the Russians continued to shoot while the civilians gathered to form a convoy, while the Russians accused the city’s defenders of using civilians as “human shields”.

And the Ukrainian governor of the Donetsk region (east), Pavlo Kirilenko, posted on Facebook, “The column for the evacuation of the civilian population could not get out of Mariupol today, because the Russians regrouped their forces and began to bombard the city.

“It is very dangerous to get people out of the country under these circumstances,” he said.

He also said that humanitarian aid from Zaporozhye, a town about a three-hour drive from Mariupol, was unable to reach.

The International Committee of the Red Cross, which is headquartered in Geneva, explains that it – as a neutral and impartial humanitarian intermediary – “facilitated dialogue between the parties regarding the safe passage of civilians”.

“Today, our teams have begun to open the evacuation route from Mariupol, before hostilities resume,” the ICRC said.

According to the organization, “the failed attempts yesterday and today confirm the lack of a detailed and practical agreement between the parties to the conflict.”

The ICRC notes that “for safe passage of civilians to take place at the required levels of confidence, the parties must agree not only on the principle, but also on the details and criteria” of the process.

In particular, the belligerents must agree on the exact time, locations, methods of evacuation, and other logistical details. The International Committee of the Red Cross says it is also important that the evacuations are voluntary and that the agreement provides for the possibility of humanitarian aid to be delivered to the cities concerned.

The organization adds that ICRC teams will remain in Mariupol and “stand ready to help facilitate new attempts if the parties reach a detailed agreement”.

According to an official with the NGO Doctors Without Borders in Ukraine, the humanitarian situation is “catastrophic” in Mariupol, with the population especially lacking water and food.