Meghan Markle and Prince Harry's visit to New York City came with an important mission.

The Duke and Duchess of Sussex made an appearance on Saturday at Global Citizen Live in Central Park, where they spoke up about the world's need for COVID-19 vaccine equity. "Every single person on this planet has a fundamental right to get this vaccine. That's the point, but that's not happening," Meghan, 40, said.

"And while in this country and many others, you can go almost anywhere and get vaccinated, billions of people around the world cannot," she continued. "This year, the world's expected to produce enough doses to meet the target of vaccinating 70% of people in every single country. But it is wrong that so much of the vaccine supply has only gone to just 10 wealthy nations so far, and not everyone else. It's just not OK."

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"Guys, we have what we need to vaccinate the world, but the experts told us, here's what's getting in the way," Harry, 37, added. "They said many countries are ready to produce vaccines at home, yet they aren't allowed to, because ultra-wealthy pharmaceutical companies are not sharing the recipes to make them. These countries have the means, the ability and the workers to start manufacturing. All they're waiting for is the vaccine intellectual property to be waived and for the vaccine technology to be transferred over. And by the way, many of these vaccines were publicly funded. They are your vaccines, you paid for them."

While the event has called for wealthier countries to commit to sharing their doses with nations most in need, Harry and Meghan called for independent international organizations to be allowed to determine where those doses are most needed.

"Just think about the millions of vaccines that have been discarded this year. That's like throwing away life vests when those around you are drowning," Meghan said.

"So, global citizens, we ask you tonight, do you think we should start treating access to the vaccine as basic human right?" Harry concluded. "When we start making decisions through that lens, where every single person deserves equal access to the vaccine, then we can achieve what is needed together, for all of us."

The New York event — which featured performances from Coldplay, Jennifer Lopez, Lizzo and more from Central Park's Great Lawn — joined a 24-hour broadcast from cities around the world calling on G7 countries and the European Union to share at least 1 billion COVID-19 vaccine doses with those most in need and support calls for a waiver on COVID-19 vaccine intellectual property rights. The campaign also called on vaccine providers to share mRNA technology with the new World Health Organization-backed transfer hub based in South Africa.

Before culminating their New York tour at Global Citizen Live, the couple visited the United Nations, where they met with UN Deputy Secretary-General Amina Mohammed during the 193-member world body's annual gathering of leaders.

"It was a lovely meeting," Meghan told reporters, according to Reuters. During the visit, they discussed the 17 Sustainable Development Goals, outlined by the UN in 2015, including ending hunger and poverty, achieving gender equality and combating climate change.

"The Deputy Secretary-General affirmed support for shared priorities around climate action, women's economic empowerment, youth engagement and mental wellbeing," the United Nations said in a statement.

The couple kicked off their visit to New York on Thursday with an early morning visit to One World Observatory at the World Trade Center with Mayor Bill de Blasio and Governor Kathy Hochul. They both dressed in black for the occasion: Meghan sported a dark turtleneck with matching trousers under a jacket with her hair pulled back into her signature low bun, while Harry sported a classic suit and tie.

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They also visited the 9/11 Museum and memorial, followed by a Thursday afternoon meeting with US Ambassador to the UN Linda Thomas-Greenfield.

The cross-country trip from their California home marked the couple's first joint public appearance since the arrival of their second child, a daughter named Lilibet Diana, in June.

New York City is a special place for Meghan. It's where she reunited with friends — including Serena Williams, Amal Clooney, Gayle King and Jessica Mulroney — in February 2019 for a baby shower ahead of the birth of son Archie.

Meghan also returned to the Big Apple in September 2019 to support Williams in the US Open final.

Harry and Meghan previously served as Campaign Chairs of Global Citizen's VAX Live: The Concert to Reunite the World, where Prince Harry gave an impassioned speech about the importance of vaccine equity.

"Over the past year, our world has experienced pain, loss and struggle — together. Now we need to recover and heal — together," the couple said in a previous statement on the subject. "We can't leave anybody behind. We will all benefit, we will all be safer, when everyone, everywhere has equal access to the vaccine."

They continued, "We must pursue equitable vaccine distribution and, in that, restore faith in our common humanity. The mission couldn't be more critical or important."