united nations - The global consequences of Russia's invasion of Ukraine were in the spotlight Tuesday at the U.N. General Assembly, as the annual debate got underway.

Leaders spoke of the urgency to get fertilizer, in particular, to the world's farmers at a reasonable price and in time for the planting season, which in some parts of the world has started already.

"Without action now, the global fertilizer shortage will quickly morph into a global food shortage," Secretary-General Antonio Guterres warned of what could lie ahead next year.

He said there are reports of farmers in West Africa and other regions cultivating fewer crops because of the price or lack of availability of fertilizers.

"Fertilizers have become three times as expensive as in 2021," Senegalese President and African Union Chairperson Macky Sall told a ministerial-level meeting on food security on the sidelines of the debate.

President of Senegal Macky Sall addresses the 77th session of the General Assembly at United Nations headquarters, Sept. 20, 2022.

Since Russia invaded Ukraine on February 24, it has imposed quotas on exports of its fertilizer, saying it wanted enough for its farmers. Moscow is a top fertilizer exporter, and the disruptions and shortages it has created have led to steep price increases on international markets. That has made fertilizer unaffordable for some smaller farmers, with the potential to dramatically decrease their harvests.

This threatens global food security, which is already in a bad way. The U.N. says more than 800 million people worldwide are suffering from hunger.

"Russia must end its illegal war against Ukraine, which has threatened an essential source of the world's food supply," Spanish Prime Minister Pedro Sanchez told the food summit. "The truth is that [Russian President Vladimir] Putin is trying to blackmail the international community with a large part of the world's food needs."

Despite calls for diplomacy, Russia signaled that it plans to persist, with plans for referendums soon for Luhansk and Donetsk to declare themselves part of Russia, which could set the stage for an escalation of the fighting.

While there are no Western sanctions on either Russian food or fertilizer exports, Moscow claims that there are. A deal signed in Istanbul on July 22 has moved more than 4 million metric tons of Ukrainian grain to international markets and is working to build confidence among shippers, insurers and buyers of Russian grain and fertilizer so they will resume at pre-invasion levels.

Guterres called for the removal of "all remaining obstacles" to the export of Russian fertilizers and their ingredients, including ammonia.

"These products are not subject to sanctions - and we are making progress in eliminating indirect effects," he said.

Appeals for peace

Turkey's President Recep Tayyip Erdogan, whose country brokered the Black Sea Grain Initiative along with the U.N., appealed Tuesday for a diplomatic end to the war.

"We would like to launch an appeal to all the international organizations and the countries of the world to support the peaceful initiatives of Turkey to settle this dispute once and for all," Erdogan told the assembly. "We need a dignified way out of this crisis and that can be possible only through a diplomatic solution which is rational, which is fair, and which is applicable."

Neither the Russian nor the Ukrainian leader are in New York this week, and no breakthroughs are expected.

"France obstinately will look for peace," said President Emmanuel Macron, who has kept diplomatic channels open with President Putin. "Our position is clear, and we want to serve this, and that's why I am engaging in a dialogue with Russia and have done so since the start of the war and over these past months, and I will continue to head this up."