"I welcome the support extended to our party by the Delhi Imam. Not only he, but all Muslims bodies are extending support to Congress," he told reporters at the airport here.
Bukhari, considered an influential religious leader, had last week appealed to Muslims to support Congress and ensure that secular votes are not divided.
Chidambaram also said he would campaign for all Congress candidates contesting the April 24 Lok Sabha polls in Tamil Nadu.
Continuing his attack on Chief Minister Jayalalithaa for not "criticising Modi or the BJP," he said his accusation that the AIADMK was BJP's "B Team," was getting "proved.