Philippe, 53, ascended the throne earlier in the day following the abdication of his father, Albert II, who reigned for the past 20 years. The White House said Obama wished the new king the very best.

　　"The United States and Belgium share a rich history and strong ties, including as NATO allies," Caitlin Hayden, a spokeswoman of the National Security Council, said in a statement.

　　"Belgium is a valued friend of the United States, and the president looks forward to continuing to deepen this bond in the years to come," she said.