Amazon.com Inc. has new drones that in coming months will deliver packages to customers in 30 minutes or less, a step toward a goal that has eluded the retailer for years.

The new drone takes off and lands vertically like a helicopter, is more stable than prior models and can spot moving objects better than humans can, making it safe, Jeff Wilke, the chief executive of the company's consumer business, said at the company's "re:MARS" conference in Las Vegas on Wednesday.

Wilke did not say where customers might see the drone in action, but Amazon made its first customer delivery by drone in the United Kingdom in 2016.