Singh, who was due to retire next year, is understood to have been mulling contesting the upcoming Lok Sabha polls either from Mumbai or Uttar Pradesh, his native state.
According to some reports, he has offers from BJP as well as Aam Aadmi Party.
"So far, my sphere of work was limited to Mumbai, now I want to serve the country. I will work for national unity, social harmony, national integration and world peace," he said.
"I have had a satisfying tenure. I will now listen to my conscience and will do as it tells me to," he added.
Responding to a question, Singh said, "I have not yet decided which party to join. But you will come to know in two to three days."
Asked about reports that he chose to be part of BJP as he was very close to the party, the city's top cop retorted, "I am close to every party and close to none."
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