Sources with knowledge of the matter have told The Wall Street Journal that Apple is moving ahead with efforts to build an Apple-branded electric vehicle, which it intends to deliver to the market by 2019.

After a year of feasibility studies, the group within Apple in charge of the electric vehicle project has been given permission to triple its staff, which currently employs 600 people, the Journal reported.

Rumors about Apple's potential expansion into the automotive industry are several months old, but news of the company's approval for a significant staff increase, as well as hints of a timeline for the development of such a car, make the company's plans seem more solid. Back in February, it was rumored that “several hundred” people were working on an electric car inside Apple's headquarters (the project was codenamed “Titan”). Apple had also recently hired former Ford designer Marc Newson at the time.

In May, Apple expressed interest in booking time at a track east of San Francisco to test autonomous and connected vehicles. In August, the company met with the California DMV to discuss autonomous vehicle regulations in the state. Still, The WSJ's sources say that Apple will develop an electric car before it comes out with an autonomous one.

Apple has already tried to insert itself into automotive scene with CarPlay, which aims to put iOS on the dashboards of other car makers.

But building a car itself would be a massive feat for a company accustomed to building consumer electronics. “It isn’t uncommon for a project of this size and complexity to miss ship-date deadlines,” The Wall Street Journal added. “People familiar with the project said there is skepticism within the team that the 2019 target is achievable.”

Apple will also have hefty competition by the time 2019 rolls around. Tesla and Nissan are already frontrunners in the electric vehicle race. Just today, Tesla invited journalists to an event next week for the Model X, the company's third production vehicle (Ars will bring you all the latest news on that next week).