"My best wishes are with Delhi and it should have full statehood. We support the demand," he told reporters after the luncheon meeting with Kejriwal at the Delhi secretariat.
Kejriwal said: "The Bihar chief minister came to congratulate us for the Delhi victory and we invited him for lunch."
Earlier on Friday, the Bihar chief minister also called on Congress president Sonia Gandhi at her residence here.
The two high-profile meetings came a day after Nitish Kumar met Prime Minister Narendra Modi to discuss issues related to his state.