Cardinal Charles Maung Bo said on Friday that the “nightmare scenario” of a global nuclear holocaust was “becoming a possibility” following Russia’s invasion of Ukraine.

The leader of the Catholic Church in strife-torn Burma said in a March 4 message that the world was on the brink of “self-annihilation.”

“The world stands at an existential crossroads. The nightmare scenario of a global nuclear holocaust is frighteningly becoming a possibility,” wrote the president of the Federation of Asian Bishops' Conferences (FABC).

“The massive attacks on Ukraine and the impending threat of use of Weapons of Mass Destruction have brought the world to the threshold of self-annihilation.”

The U.N. refugee agency reported on March 3 that more than 1,164,000 people have fled Ukraine since Russian President Vladimir Putin ordered a full-scale invasion on Feb. 24. Over 55% of them have found refuge in Poland, which shares a 332-mile border with the country.

U.N. human rights chief Michelle Bachelet said on March 3 that her office had “recorded and confirmed 752 civilian casualties, including 227 killed — 15 of them children.”

The chief prosecutor of the International Criminal Court in the Hague, Netherlands, announced on March 2 that he was opening an investigation into alleged war crimes by Russia.

Facing military setbacks and international condemnation, Putin told defense chiefs on Feb. 27 to put Russia’s nuclear forces on “special alert.”

Cardinal Bo, the archbishop of Yangon, Burma’s former capital city, said that the Ukraine conflict had to end.

“We join Pope Francis in appealing to the rulers of Russia — and to all others who believe in the power of violence to solve world problems through peaceful means and dialogue in the U.N.,” he wrote. 

“We are heartened by the united response of the world community in the U.N., where more than 140 countries voted against this war of attrition which threatens to destroy human security, respect for global institutions.”

The 73-year-old cardinal’s own nation, officially known as Myanmar, was itself thrown into turmoil when the military staged a coup on Feb. 1, 2021. 

According to the advocacy group Assistance Association for Political Prisoners, almost 1,600 people have been killed in a crackdown on protesters and more than 12,000 arrested in the Southeast Asian country as of March 3.

“Let not history repeat itself in the 21st century,” Cardinal Bo said. “The world has suffered a lot, encountering the multidimensional crisis of a pandemic that killed millions, dealing a blow to the economy, impoverishing millions. This is the time for global healing, not hurting.” 

Appealing directly to Putin, Cardinal Bo noted that Russia is one of five permanent members of the U.N. Security Council, which has the task of “promoting world peace and ensuring the rights of every nation.”

“We appeal to Russia to cease attacks on Ukraine, and return to the U.N. for peaceful resolution of all issues,” he wrote. “Peace is always possible, peace is the only way for humanity’s future.”