"BJP/NDA's cheap sense of politics has reached ludicrous and ridiculous proportions. Neither My wife, sons nor me have anything whatsoever to do with Gitanjali or Nirav Modi companies," he said in a statement.
Singhvi said Nirav Modis company was a tenant of a Kamla Mills property owned by Adwait Holdings in which his wife and sons are directors.
BJP leader and Union Minister Nirmala Sitharaman alleged that Nirav Modi-run Firestar Diamond International had taken on lease a property of Adwait Holdings, a company in which Congress leader Abhishek Singhvi's wife is a director.
Singhvi said Adwait Holdings owns a commercial property at Parel, which was rented by Nirav Modi's company many years ago.
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"Neither I nor any member of my family has any interest in or relation to Nirav Modi or his companies. His company was a tenant in some commercial property owned by our family company. This tenancy ended in December 2017.
"Sensationalism, ignorance and falsehood has exceeded all limits in this irresponsible charge," he said, threatening Sitharaman and her colleagues of civil and criminal defamation for making "ill-considered, ignorant and patently false allegations".
"I reserve my rights to take all such appropriate legal action against the latter and all parts of the media which carry such false and maliciously defamatory allegations," Singhvi said in a statement.
Nirav Modi, 46, a regular feature on the lists of rich and famous Indians since 2013, was booked by the CBI, along with wife, brother and Gitanjali Group promoter Mehul Choksi on January 31, for allegedly cheating the state-run PNB to the tune of Rs 280 crore.
The jewellery designer is understood to be a citizen of the country but his brother Nishal and wife Ami are not Indian nationals. They all left India between January 1 and 6, the CBI had said.