The U.N. chief said groups such as Islamic State, al-Qaida and others have quickly made Africa a major threat to peace.
African leaders say they have a market-based plan to fight human-caused global warming that will spread economic development among millions of people on the continent.
The suspension, a typical reaction to Africa's military coups, bars Niger from voting on the A.U.'s proposals.
African Union and West African regional bloc leaders supported deployment of a standby military force and demanded that Niger's junta release the ousted president.
More than 300 accounts of heads of state, government leaders and their institutions, plus some 40 major international organizations and their leaders were slated to be demoted.
As the continent faces a raft of complications, the African Union's ambitious goal of tackling structural root causes and drivers of conflict for sustainable development is in doubt.
Mozambique, which holds the U.N. Security Council's monthly revolving presidency, hosted a discussion on how to strengthen efforts between the United Nations and regional organizations at curbing terrorism and violent extremism.
The staggering numbers include 129,000 people "facing starvation and staring death in the eyes," while 11.9 million children under five likely will face acute malnutrition in 2023.
Women and girls still don't get the support they need, U.N. Secretary-General António Guterres said, and African nations cannot develop with "one hand tied behind their backs."
At last month's G-20 summit hosted by Indonesia, South Africa's President Cyril Ramaphosa pushed for A.U. membership as a needed step to confront climate change.
Despite a steady decline in piracy in the Gulf of Guinea in recent years, nations must accelerate efforts to counter the region's nearly US$2 billion a year in losses, senior U.N. officials urged diplomats in charge of international security.