The Samajwadi Party appointed actor Sanjay Dutt as its national general secretary.

Dutt, who was refused permission by the Supreme Court to contest the elections because of his conviction under the Arms Act, said: "Mein dil se kam karoonga aur sach ke liye kam karoonga (I will work with my heart and for the truth)."

Also a day after the Supreme Court disallowed him from contesting elections because of his conviction in a criminal case, Bollywood star Sanjay Dutt Wednesday alleged that a senior Congress minister had threatened him if he did not join that party.

In an interview to television channel NDTV, Dutt said he had tapes of the conversation he had with the minister who threatened him that court cases would go against him if he did not join the Congress.

Refusing to identify the minister, Dutt said: "I did a sting operation on the minister."

He added that he "wore a taping device to expose the minister".

Dutt was given a ticket by the Samajwadi Party to contest the Lok Sabha election from Lucknow, but will not be able to fight after the Supreme Court Tuesday refused to suspend his conviction for owning illegal arms in the run-up to the 1993 serial bombings in Mumbai.

"I did a sting operation against a union minister. I did the sting operation to expose the bias of the minister. The minister told me (the) verdict would go against me if I contested for SP (Samajwadi Party)," Dutt told the channel.

"We will not name the minister," Samajwadi Party general secretary Amar Singh added.

On a bitter note, Dutt said the Congress did not treat well his father, late actor and central minister Sunil Dutt.

"The Congress killed my father. Sunil Dutt never forgave them for Sanjay Nirupam (the Shiv Sena leader in Mumbai who joined the Congress)," he said.

Talking about the possible Samajwadi Party candidate for Lucknow in his place, Dutt said: "I don't mind (wife) Maanyata contesting if the party decides so." He, however, added: "Maanyata will focus on the home. I will campaign."

On speculation that veteran actress and party leader Jaya Bachchan could be nominated, Amar Singh said: "Jaya Bachchan contesting from Lucknow (is) out of the question. Jaya contesting would drag the rest of the (Bachchan) family into politics. Jaya contesting the poll would complicate the Gandhi-Bachchan equation."