"We must make sure funds go where they are needed most. Latest reports indicate that there has been a $5 trillion surge in the wealth of the world's richest in the past year," Guterres told a UN meeting on financing for development.
"I urge governments to consider a solidarity or wealth tax on those who have profited during the pandemic, to reduce extreme inequalities," he said.
Guterres again said the Group of 20 rich nations and big emerging powers should extend debt service suspension into 2022 and to expand it to help both developing and middle-income economies recover from the pandemic.
"But we need to go beyond debt relief," Guterres said. "We urgently need to strengthen the international debt architecture to end the deadly cycles of debt waves, global debt crises and lost decades."
Guterres also repeated his call for COVID-19 vaccines to be made available to all countries and appealed for more money to fully fund the COVAX vaccine sharing facility.
"Advancing an equitable global response and recovery from the pandemic is putting multilateralism to the test. So far, it is a test we have failed. The vaccination effort is one example," he said. "Just 10 countries across the world account for around 75 percent of global vaccinations."