"The Commission has come to the conclusion that your comments violate the said MCC norms. The Commission has, therefore, decided to convey its displeasure to you for your comments and expects that you shall exercise caution in future," the poll panel said in a letter to the NITI Aayog Vice Chairman.
On March 27, the poll panel had sought Kumar's response on his remarks in which he had attacked the Congress over its minimum income guarantee promise.
Kumar had slammed the Congress' anti-poverty scheme Nyay, saying that its cost at 2 per cent of the GDP and 13 per cent of the Budget will ensure that the real needs of the people remained unsatisfied.
The EC had felt that since Kumar is a bureaucrat, his remarks were prima facie violative of the model code. The EC said it had considered his reply and did not find it to be "satisfactory".
"The spirit of the model code of conduct requires all public servants to ensure the sanctity of the electoral process, not to either engage in or appear to engage in any activity that disturbs or appears to disturb the level playing field of conduct of election or creates doubts in the minds of stakeholders about the integrity of the electoral process.
"Public servants should not only be impartial in their conduct but also in their public utterances, which was found wanting in the instant case," the poll panel said.
Congress president Rahul Gandhi had on March 25 announced that 20 per cent families belonging to the poorest category will be given Rs 72,000 each annually as minimum income if his party comes to power.
(With inputs from agencies)