The Bharatiya Janata Party (BJP) on Tuesday asked the Congress party to explain the alleged links between party President Sonia Gandhi's son-in-law Robert Vadra and arms dealer Sanjay Bhandari."Why is the senior leadership of the Congress silent on the Vadra matter," Defence Minister Nirmala Sitharaman asked, referring to media reports about the reported financial links between Vadra and the arms dealer, who fled to the UK. Bhandari, who ran a defence consultancy firm called Offset India Solutions, faces an investigation into a defence deal in which he is alleged to have received kickbacks after swinging the jet trainer deal for Swiss company Pilatus.In the latest media report exposing the Bhandari-Vadra links, TimesNow TV news channel claimed to have accessed emails to establish that the two were in close touch with each other. The channel claimed that the emails show that Bhandari bought Vadra air tickets worth Rs 8 lakh for an Emirates flight in August 2012.The Congress has not reacted to the TimesNow report."Is the Congress leadership, by being silent, implying they knew of it?," Sitharaman asked.She said while it was for the probe agencies like the CBI to establish the links between the two, she was only asking the Congress to break its silence over the issue."I am not establishing the link. We will have to ask the Home Ministry and the CBI about that."