The former Samajwadi Party leader and a sitting Rajya Sabha member, an accused in the cash-for-vote scandal, was on Thursday granted interim bail till Sept 19 by a Delhi court.
Singh was languishing in the Tihar jail since Sept 6 and later when he complained of chest pain was hospitalized at the All India Institute of Medical Sciences (AIIMS).
Singh is a family friend of the Bachchans.
Earlier actor turned politician Jaya Prada visited him in the hospital and said his friends for whom he had worked all life had deserted him in his time of crisis.
Singh was asked by the court to apply for regular bail on Sept 19.
He has been barred from foreign travels and had to furnish a personal bond of Rs 2 lakh.
On late Monday last, Singh was taken to AIIMS and admitted to a private ward.