Sources said the two leaders had separately called up Kejriwal and lauded his stunning victory in the elections in which the BJP faced a humiliating defeat.
After organisational changes in BJP, both Advani and Joshi are now part of the party's newly-formed 'margdarshak mandal', a group formed to guide the party after they were ousted from BJP's top decision-making bodies - the Parliamentary Board and the Central Election Committee.
Prime Minister Narendra Modi has already congratulated Kejriwal and the AAP leader also called on him today morning.