NEW YORK - David Beckham, Millie Bobby Brown and Hugh Jackman are among celebrities and world leaders announced Wednesday as participants and official supporters of the UNICEF initiative World Children's Day.

The organization said events around the globe will focus on child takeovers to mark the day Monday, including a gathering at the United Nations in New York. That's where UN Secretary-General Antonio Guterres will welcome children and singer-songwriters Chloe x Halle will perform a new track written for the occasion.

Young people in Geneva, meanwhile, will take over the Palais des Nations to perform a special cover of Pink's hit "What About Us."

In Spain, children will join Leo Messi and others on the powerhouse soccer team FC Barcelona for a practice session, while in India, cricket will be the game for 22 child athletes who will play with legendary cricketer and UNICEF goodwill ambassador Sachin Tendulkar.

Brown, who appears on the Netflix series "Stranger Things," will kick off the day in Australia. Jackman is lending his voice via video to a fundraiser focused on providing clean water to those in need, to take place in gyms around the world on Saturday.

"I am so excited for the first-ever global celebration of World Children's Day on Nov. 20 with UNICEF," Brown said in a statement. "It's our day, everyone! A day for us to raise our voices and unite. So let's do it - in our schools, with our friends, with our families!"

Beckham, a UNICEF goodwill ambassador, will appear in a short film with children. Other events are planned for Copenhagen and Accra, where 10 children from eight African countries will tell the world about the continent in a series of Ted Talk-style appearances called Africa Dialogues. - AP