At a time when L.K. Advani has undertaken to revive the BJP’s fortunes, Jana Sangh president Balraj Madhok has suggested that he and former PM A.B. Vajpayee return to the ‘‘truly’’ saffron party.‘‘The Bharatiya Jana Sangh is the only nationalist party. All others, including Congress and BJP, are using secularism as a political tool,’’ Madhok said on Thursday, at the occasion of the 54th foundation day of the Jana Sangh. He said it would be wrong to call the BJP an Opposition party. There is no difference between BJP and other so-called secular parties; the BJP had given up Hindutva, he said.