Hiraben died at a hospital in Ahmedabad on Friday morning. She was 99.
"Deeply saddened to hear about the demise of #HirabenModi, mother of Prime Minister Shri Narendra Modi ji. My thoughts and prayers are with the bereaved family members and friends during this hour of grief, #OmShanti," he tweeted.
Patnaik asked minister Srikant Sahu to attend the funeral of Hiraben on his behalf.