At an occasion in New York, Prince William gave a warning about the most "pressing existential threat we face;" this came just hours after Prince Harry delivered a passionate address in the same city.

A plea to rescue species, ecosystems, and natural resources that are "buckling under the pressure of our actions" was issued by the Prince of Wales, PEOPLE Magazine. Just hours after his estranged brother, the Duke of Sussex, delivered a speech in person in the city, he made the remarks in a video message that was shown during a United Nations General Assembly event.

During his impassioned statement at Tuesday's Clinton Global Initiative, PrinceHarry warned that "our kids can't wait" and asked the globe to address the "pervasive threat" that children face in the digital age.

At Tuesday's third annual Earthshot Innovation Summit in New York, Prince William revealed the winner of his environmental Earthshot Prize via video message. While his brother decided to host a slew of events in New York during the week of the United Nations General Assembly, he opted not to travel to the United States this week but did attend last year's event in the Big Apple.

"Thankfully, in 2022 the world adopted the Biodiversity Plan in Montreal and committed to transformative action to halt and reverse biodiversity loss by 2030. But, we now have just five years to deliver on our collective promise,” Prince William told a reception of world and indigenous leaders gathered to discuss biodiversity.

"We must act to save our rivers, oceans, savannas, mangroves and forests, as well as the communities that protect and live alongside them. We must act with urgency to protect at least 30% of our land, inland waters, and ocean by 2030,” the Prince of Wales added.

Among the prince's demands were an end to the "unsustainable production and consumption of natural resources," improved collaboration with local and indigenous communities and "traditional custodians of biodiversity," the redistribution of funds from "harmful subsidies" that are "wreaking havoc on our natural world" to "alternative solutions," and more funding for those initiatives.

While on an East Coast tour without the Duchess of Sussex, Prince Harry had two engagements in New York City during UN General Assembly High-Level Week and Climate Week, the video message arrived, HELLO! Magazine reported.

At a United Nations General Assembly side event, Prince Harry spoke about Lesotho, the poor southern African nation where he established his Sentebale charity to aid Aids orphans. He also met with members of the Travalyst organization, which he established to promote more sustainable practices in the tourism industry.

On Monday, he also addressed a ceremony for the Diana Award and the Halo Trust, a nonprofit fighting against landmines. There is tension between Prince Harry and his father, the King, and he has a troubled relationship with his elder brother, Prince William. The annual WellChild awards are next Monday, and the duke is planning a short trip to the UK to attend.