In a statement released at the end of a three-day meeting on Germany's Baltic Sea coast, the G-7 nations also called on China not to help Russia, including by undermining international sanctions or justifying Moscow's actions in Ukraine.
"Russia's war of aggression has generated one of the most severe food and energy crises in recent history which now threatens those most vulnerable across the globe," the group said.
"We are determined to accelerate a coordinated multilateral response to preserve global food security and stand by our most vulnerable partners in this respect," it added.
The G-7 asked Beijing to support the sovereignty and independence of Ukraine, and "not to assist Russia in its war of aggression."
The group, which comprises Britain, Canada, France, Germany, Italy, Japan and the United States, also called on China "to desist from engaging in information manipulation, disinformation and other means to legitimise Russia's war of aggression against Ukraine."
The meeting in Weissenhaus, northeast of Hamburg, was billed as an opportunity for officials to discuss the broader implications of the war for geopolitics, energy and food security, and ongoing international efforts to tackle climate change and the pandemic.
In a series of closing statements, the G-7 nations also addressed a wide range of global problems from the situation in Afghanistan to tensions in the Middle East.
On Friday, Ukrainian Foreign Minister Dmytro Kuleba appealed to friendly countries to provide more military support to Kyiv and increase the pressure on Russia, including by seizing its assets abroad to pay for rebuilding Ukraine.
Kuleba said his country remains willing to talk to Russia about unblocking grain supplies stuck in Ukraine's silos and also about reaching a political agreement to end the war itself, but had so far received "no positive feedback" from Moscow.
German Chancellor Olaf Scholz said in an interview published on Saturday that he had not detected any change in Putin's stance recently.
Scholz, who spoke at length by phone with the Russian leader, told a German news site that Putin had failed to achieve the military objectives he set out at the start of the war while losing more Russian soldiers than the Soviet Union did during its decade-long campaign in Afghanistan.
"Putin should slowly begin to understand that the only way out of this situation is through an agreement with Ukraine," Scholz was quoted as saying.
The G-7 meeting was attended by top diplomats from Britain, Canada, France, Germany, Italy, Japan and the United States. Aside from Kuleba, representatives from Moldova and Indonesia were also invited to participate in some of the talks.
