"Modiji ki agni pariksha pahle din se li ja rahi hai (Modi is facing a trial by fire from day one)," Das said when asked about the forthcoming Bihar elections and criticism of Modi's performance by rival parties.
He was talking to reporters after he held a 'Janata Durbar' at the Circuit House here.
Making an apparent refernce to Congress, Das regretted that the trial was being taken by those who ruled the country for six decades.
Criticising the prevailing state of affairs in Bihar, he said there was no ring master in that state and the ruling alliance constituents were making tall claims on their own.
He attributed politics of casteism, regionalism as reasons for the backwardness of Bihar, while assuring all round development if NDA was voted to power.