On Nelson Mandela Day at the United Nations, Prince Harry urges world leaders to “be brave” in the face of climate change and other crises.

Britain’s Prince Harry, the Duke of Sussex on Monday honored South Africa’s late anti-apartheid icon by delivering Nelson Mandela’s International Day keynote address to the United Nations General Assembly. Harry’s wife Meghan, the Duchess of Sussex, accompanied the prince on his visit to the UN headquarters in New York.

Harry hailed the pro-democracy legacy of the South African crusader, who became his country’s first black president after languishing 27 years in prison for his efforts to crush the racist apartheid regime. The UN has declared July 18 – the late leader’s birthday – as an international day to honor his memory and remarkable struggle for freedom and equality.

“We are living through a pandemic that continues to devastate communities in all parts of the world. climate change wreak havoc on our planet, with the most vulnerable suffering the most; the few Weaponizing lies and disinformation at the expense of the many and the terrible war in Ukraine to roll back the constitution rights here in the United Stateswe are witnessing a global attack on democracy and freedom, the core of Mandela’s life,” said Harry.

The late Princess Diana, Harry’s mother, met Mandela in 1997, just before she died in a car accident in Paris. Harry and Meghan toured South Africa in 2019 while still performing official royal duties and met Graça Machel, Mandela’s widow.

Harry and Meghan gave up their duties and some privileges as “working members” of the British royal family in 2020 and emigrated to Southern California.

Monday’s keynote speech was an increasingly rare appearance on the world stage for Harry. He referenced his mother’s efforts to address the ugly legacy of racial separatism and also spoke at length about climate change and tackling hunger around the world.

“As we sit here today, our world is on fire again,” Harry said Forest fires are raging in southern Europe and his homeland is baking in record heat. “These historic weather events are no longer historic, they are part of our daily lives and this crisis will only get worse unless our leaders take the lead; unless the countries represented by the seats in this sacred hall make the decisions—the daring, transformative decisions that our world must save humanity. These decisions may not fit into the agendas of any political party, they may provoke opposition from powerful interests. But what is right is not up for debate, and neither is the science. The only question is whether we are brave enough and wise enough to do what is necessary.”

That, Harry said, is what Nelson Mandela did: he acted.

“In her strength and in her actions, Mandela’s legacy shines as brightly as ever. You are my lifeboat. I hope they can be yours too,” said the king. “It’s more important than ever that we seek a goal bigger than ourselves and get to work.”

The UN Mission from South Africa said Monday’s two-hour event will address Mandela’s legacy, as well as racial intolerance, the growing gap between rich and poor, and hunger and food insecurity.

“Our world today is overshadowed by wars, overwhelmed by emergencies, plagued by racism, discrimination, poverty and inequalities, and threatened by climate catastrophes,” UN Secretary-General Antonio Guterres said in his speech.

He proclaimed Mandela “a giant of our time” and a “moral compass” for the way forward.

“On Nelson Mandela’s birthday, the United States joins the international community in honoring the enduring legacy and inspiration of a dedicated peacemaker, human rights activist and defender of democracy,” said U.S. Ambassador to the United Nations Linda Thomas-Greenfield. in a statement. “Let us honor his life by recognizing that no matter who or where we are, we all have the responsibility and power to make a difference in our communities and build a better world for all.”