Russian President Vladimir Putin's invasion of Ukraine left dozens of countries teetering on the edge of famine.
That was until a July ceasefire agreement seemed like it would ease the pressure felt by billions of people.
However, at the weekend, Russia cancelled the deal in a move that's been described as "blackmailing the world with hunger".
Here's the situation as it stands.
Russia and Ukraine help feed the world
First, a very quick history lesson on grain exports out of Russia and Ukraine.
Both countries have emerged as grain-producing heavyweights in the decades after the fall of the Soviet Union.
In 2001, they accounted for roughly 1 per cent of the world's wheat exports.
Now, combined, the nations account for about 26 per cent of the world's wheat exports, with Russia being the world's leading exporter.
Ukraine was also exporting more than 5 million metric tonnes of wheat each month before Russia's invasion and, among other things, it is the largest exporter of sunflower products.
For centuries, Ukraine has been known as "the breadbasket of Europe" because it is home to about a quarter of the world's super-fertile "chernozem" soil.
The invasion put pressure on global food prices
Shock waves from Russia's invasion of Ukraine have seen increased food insecurity.
The United Nations warned it had pushed 47 million people into a stage of "acute hunger" within months of the invasion.
Its invasion meant Western countries closed ports to Russian ships.
Shipments out of Ukraine were closed as ports were blockaded, occupied or under attack by Russian forces.
This chaos came as supply chains were already under stress, just as the world began to open up after the worst of the pandemic.
Türkiye and the UN step in to open a grain corridor
As alarm at global food shortages increased, Türkiye and the UN stepped in to broker a deal with Russia, allowing Ukraine to open ports to the Black Sea.
The deal ensured safe passage for ships in and out of three Ukranian ports: Odesa, Chornomorsk and Yuzhny.
Under the de facto ceasefire, grain shipments were allowed travel through Black Sea, to Türkiye's Bosphorus Strait, and off to world markets.
The agreement has allowed more than 9 million tonnes of grain in 397 ships to safely leave Ukrainian ports since July.
It brought global food prices down by about 15 per cent from their peak in March, according to the UN.
The deal was signed on July 22, and was due to run for 120 days, with the UN expecting it to be renewed unless the war had ended.
"The aim of these agreements … is to provide some kind of solace to the global south," said a UN official.
Russia and the UN also signed a memorandum of understanding, committing the UN to facilitating unimpeded access of Russian fertiliser and other products to global markets.
Why has Russia called the deal off?
Russia says its Black Sea Fleet was attacked by 16 drones near Sevastopol — roughly 220km from the grain corridor — at the weekend.
It says it repelled the attacks with just minor damage to a minesweeper, but added that the ships targeted were involved in ensuring the grain corridor.
Russia also says British navy "specialists" had helped coordinate what it calls a "terror attack".
So it has cancelled the grain corridor deal early. The deal had been due to run until mid-November.
Ukraine has not claimed responsibility for the reported drone attacks.
Ukraine, UN and the US condemn the decision
Ukrainian President Volodymyr Zelenskyy says Russia's move puts the world back at the edge of a food crisis.
So far, Ukraine's Infrastructure Ministry says 218 ships involved in grain exports have been blocked.
All up, 22 ships are loaded and stuck at ports, 95 are loaded and have departed from ports, and 101 ships are awaiting inspection.
"There are now 218 pieces of evidence that Russia does not want any genuine agreements," Mr Zelenskyy said.
One of the blocked ships, carrying 40,000 tonnes of grain bound for Ethiopia under a UN aid program, was prevented from leaving Ukraine at the weekend.
"Russia is the only culprit for the fact that food will now become more expensive for different people in a vast area from West Africa to East Asia," Mr Zelenskyy said.
"Russia is the reason why people — in particular in Ethiopia, Yemen or Somalia — are left with catastrophic food shortages."
Mr Zelenskyy's chief of staff, Andriy Yermak, accused Russia of inventing "fictitious terrorist attacks on its own facilities".
Ukraine's Foreign Minister Dmytro Kuleba said Moscow was using a "false pretext" to sink the deal.
"I call on all states to demand Russia stop its 'hunger games' and recommit to its obligations," Mr Kuleba said.
US President Joe Biden called the move by Russia as "purely outrageous", saying it would increase starvation, and US Secretary of State Antony Blinken accused Russia of weaponising food.
So, what happens now?
No ships moved at the weekend, but the UN said it had agreed with Ukraine and Türkiye on a movement plan for 16 vessels.
UN spokesperson Stephane Dujarric said in a statement that Secretary-General António Guterres had made "intense contacts" aiming to end the Russian suspension of the agreement.
"The Secretary-General is deeply concerned about the ongoing situation regarding the Black Sea Grain Initiative," Mr Dujarric said.
Following Russia's announcement, wheat prices jumped and they could continue to increase.
"Depending on the scramble to replace planned Ukraine cargoes, prices might even head into double digits for a period," said Commonwealth Bank of Australia strategist Tobin Gorey.
Turkish Defence Minister Hulusi Akar is in talks with his counterparts to "solve the problem and to continue the grain initiative".
Türkiye added that no more grain ships were expected to leave Ukraine.
