The project has been code-named Titan and its leaders have been given permission to triple the 600-person team, the WSJ said, citing people familiar with the matter.

For Apple, a "ship date" doesn't necessarily mean the date that customers receive a new product; it can also mean the date that engineers sign off on the product's main features, the WSJ said.

Apple spent more than a year investigating the feasibility of an Apple-branded car, including meeting with two groups of government officials in California, according to the Journal.

Sources told Reuters in August that Apple was developing a car and studying self-driving technology, but it was unclear if the iPhone maker was designing a vehicle that could drive itself.

Apple was not immediately available for comment.

The Cupertino, California-based company doesn't currently plan to make its first electric vehicle fully autonomous, WSJ said on Monday.

Apple has been consistently hiring car experts as part of its effort to build a team in automated driving.

Apple has hired this year Megan McClain, a former Volkswagen AG engineer with expertise in automated driving, and Vinay Palakkode, a graduate researcher at Carnegie Mellon University, a hub of automated driving research.

Apple also hired a senior engineer from electric car maker Tesla Motors Inc, according to a LinkedIn posting.

Apple's shares were up 1.3 percent at $114.98 on the Nasdaq.