NEW YORK - Britain's Prince William sat down with President Obama in Washington on Monday and unveiled an effort to curtail illegal wildlife trading while his wife, Kate, made an impression of a down-to-earth duchess on preschoolers and prominent British expats in New York.

In the first full - very full - day of the popular royal couple's first visit to either place, William went to the White House and spoke at a World Bank conference. Kate wrapped Christmas gifts and helped children decorate picture frames while touring a child development center with New York City's first lady, then talked technology, theater and more with a British-success-story guest list at a lunch at the consul general's home.

The Duke and Duchess of Cambridge are on their first official trip to the United States since 2011. William, speaking at the World Bank, announced a task force to develop recommendations within a year on how the transportation industry can help stop wildlife trafficking, calling it "one of the most insidious forms of corruption and criminality."

Meanwhile, the duchess and city first lady Chirlane McCray met with families and heard about the work of the Northside Center for Child Development, which offers mental health and educational services.

"Very nice to meet you," Kate told a classroom of 3- and 4-year-olds, who were embellishing picture frames with stickers.

After encouraging a boy named Sammy in his work, the duchess, who is expecting the couple's second child, turned to a girl named April.

"Where should I put this one?" Kate asked, affixing a sticker.

The royals also attended an early evening reception highlighting wildlife conservation efforts with former Secretary of State Hillary Rodham Clinton and her daughter, Chelsea.

During the event at the British consul general's residence, William made a brief speech on the plight of the world's most iconic species being "butchered in the name of trinkets and medicine" before ending it on a lighter note.

"I'm off to shoot some hoops now, or whatever it is you Americans say," he quipped.

The royals' schedule for their three-day trip includes a visit to the National Sept. 11 Memorial and Museum, a visit to showcase arts education at a youth organization, a Cleveland Cavaliers-Brooklyn Nets game, and a black-tie fund-raiser for their alma mater, the University of St. Andrews.