The commander of Ukrainian forces still holding off Russian troops in Mariupol made an urgent plea Wednesday to world leaders, including Pope Francis, and said there are still 600 soldiers and civilians stuck in the deadly standoff.

Serhiy Volyna, commander of the 36th separate Marine brigade, said his troops, along with civilians caught in the crossfire at the Azovstal steel plant, were "surrounded" by Russian forces.

Mariupol Ukraine

A part of a destroyed tank and a burned vehicle sit in an area controlled by Russian-backed separatist forces in Mariupol, Ukraine, on Saturday, April 23. (AP/Alexei Alexandrov)

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Over 1,000 people were estimated to have taken shelter in the tunnels under the steel plant and have been unable to evacuate under Russia’s constant barrage of missile strikes.

Volyna said that not only did the elderly and injured need attention but also noted they were running short on food, water and defenses. 

In a Facebook post, the commander pointed to other examples of extraordinary evacuations, including the infamous World War II Miracle of Dunkirk, when more than 338,000 British and French troops were evacuated after being cornered by German forces on a beach in France. 

"Winston Churchill, in a famous speech in 1940, called the events in Dunkirk ‘a wonderful salvation’," Volyna wrote Wednesday. "Churchill's praises were intended for a rescue operation in which 338,226 French and British soldiers were evacuated from the beach and harbor of the city of Dunkirk in France.

"2022 Mariupol...," he concluded. 

RUSSIA ATTEMPTING TO 'STORM AGAIN AND AGAIN' MARIUPOL STEEL FACTORY, UKRAINE OFFICIAL SAYS

A Mariupol official said Russian forces continue to attempt to "storm again and again" the steel factory, despite repeated calls from the United Nations, Ukrainian officials and humanitarian groups to allow for safe evacuation for those trapped inside. 

Petro Andryushchenko, an adviser to Mariupol’s mayor, said street fighting had again broken out in the port city. 

U.N. Secretary-General Antonio Guterres met with Russian President Vladimir Putin this week to discuss opening humanitarian corridors for evacuations.

The U.N. said Putin "agreed, in principle, to the involvement of the United Nations and the International Committee for the Red Cross in the evacuation of civilians from the Azovstal plant in Mariupol."

Mariupol steel factory Ukraine

Smoke rises above the Mariupol Azovstal Iron and Steel Works factory on April 21. (REUTERS/Alexander Ermochenko)

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But on Wednesday, Kremlin spokesman Dmitry Peskov dashed hopes for a timely evacuation effort, saying only that Russia would "consider" it.

"No specific agreements have been reached in this area," he told reporters. 

Fox News' Matthew Finn contributed to this report.