New Delhi, Jul 6 (IANS): Tesla CEO Elon Musk has finally admitted that developing a safe and reliable self-driving car is indeed a difficult task.

In an earnings call in January, Musk had told investors that he was "highly confident the car will be able to drive itself with reliability in excess of human this year".

In a latest tweet, Musk said: "Generalized self-driving is a hard problem, as it requires solving a large part of real-world AI. Didn't expect it to be so hard, but the difficulty is obvious in retrospect."

"Nothing has more degrees of freedom than reality," Musk added.

Despite tall claims made by Musk over Twitter about the full self-driving technology, electric car-maker Tesla recently admitted that such claims do not match up with the engineering reality.

"Elon's tweet does not match engineering reality per CJ. Tesla is at Level 2 currently," Tesla's director of Autopilot software CJ Moore told the California Department of Motor Vehicles (DMV)

Level 2 technology refers to a semi-automated driving system, which requires supervision by a human driver.

Tesla vehicles come with a driver assistance system called 'Autopilot' that enhances safety and convenience behind the wheel. When used properly, Autopilot reduces your overall workload as a driver.

For an additional $10,000, people can buy "full self-driving" or FSD, that Musk promises will deliver full autonomous driving capabilities.

Full Self-Driving capabilities include navigate on Autopilot, Auto Lane Change, Summon (moves your car in and out of a tight space using the mobile app or key),

However, Tesla vehicles are still not driving on their own and "are far from reaching that level of autonomy".

Tesla, however, is unlikely to achieve Level 5 (L5) autonomy, in which its cars can drive themselves anywhere without any human supervision by the end of 2021.