Leaders of Australia, India, Japan and the United States expanded joint security steps in Asia's trade-rich waters as outgoing U.S. President Joe Biden hosted counterparts from the Quad grouping established due to shared concerns about China.

President Joe Biden is convening the leaders of Australia, India and Japan for a Quad summit in his hometown of Wilmington, Delaware, this weekend, aiming to put a final stamp on an alliance he hopes will endure beyond his presidency.

"It will survive way beyond November," Mr. Biden declared of the Quad as the leaders gathered at the Archmere Academy, his high school alma mater.