Uttarakhand Finance Minister Prakash Pant passed away in the US during the early hours of Tuesday.
Prakash was in US undergoing a lung treatment.
Three-day state mourning as well as one day holiday (Thursday) has been announced in the state of Uttarakhand.
It is reported he has gone to US for a medical treatment sometime in the last week of may.
Prakash was suffering from lung ailment from a long time and did not campaign for the party in the Lok Sabha elections as well.
There have been reports of him struggling at work during the early months of the year.
Prakash had almost fainted during a speech in the state assembly.
Prakash Pant was said to be one of the front runners in the race to be the chief minister of the state in 2017.