Senior police officers denied reports that the man, named Ambaresh, had engaged in lewd or offensive talk.

The officers said he did not even know that the number was Ms Rabbani Khar's.

Pakistan's foreign office had asked India to inquire into the call, which was made two months ago.

Ambaresh said he got the shock of his life when police began investigating his background and questioned him about the call made to Ms Rabbani Khar from his mobile phone.

He works as a tutor at an exam-coaching institute and said it was possible pranksters had used his phone to call the minister.

He told local media: "Neither have I heard of Ms Rabbani Khar nor do I know Urdu or English to abuse her. I don't know if some student who resides at this centre used my phone."

Officers from the intelligence bureau and the crime branch tracked him down after Pakistan requested an inquiry into the call.

"He is clear. There is no case against him," police officer SB Bisnalli told the BBC.

Earlier, a newspaper report said the call had lasted 15 minutes and the caller had abused Ms Rabbani Khar.

"This is not true at all. It was a call made by mistake," a crime branch official said.

Ms Rabbani Khar, 34, was appointed foreign minister last year - the first woman in Pakistan to hold the position.