Leader of Opposition in the Uttarakhand Assembly Indira Hridayesh passed away after suffering a cardiac arrest in New Delhi on Sunday.

The 80-year-old senior Congress leader died at the Uttarakhand Sadan in New Delhi where she had gone to attend a party meeting, Pradesh Congress vice president Suryakant Dhasmana said quoting her son Sumit Hridayesh.

Hridayesh was a Congress MLA from Haldwani and one of the senior most Congress leaders from the state.

She had tested positive for Covid-19 in April this year and had undergone a heart surgery after her recovery.

Hridayesh had attended a party meeting chaired by party in-charge for Uttarakhand Devendra Yadav in New Delhi on Saturday.

Prime Minister Narendra Modi and Congress leader Rahul Gandhi condoled her demise and lauded her contributions.

"Dr. Indira Hridayesh Ji was at the forefront of several community service efforts. She made a mark as an effective legislator and also had rich administrative experience. Saddened by her demise. Condolences to her family and supporters. Om Shanti," the prime minister said in a tweet.

In a tweet in Hindi, Rahul Gandhi said, "Received the sad news about the demise of Dr Indira Hridayesh, a strong link of the Congress party in Uttarakhand. She worked till the end for public service and the Congress family. Her social and political contributions are an inspiration. Condolences to her loved ones".

Congress general secretary and former state chief minister Harish Rawat said it is an irreparable loss for the country and the state.

Rawat said she has been a part of the Congress family for over four decades, first in Uttar Pradesh and then in Uttarakhand and was the voice of teachers.

Condoling her demise, AICC general secretary Priyanka Gandhi Vadra said the Congress has lost a brave leader and popular public representative.

Expressing grief at her death, Chief Minister Tirath Singh Rawat said she played a significant role in the politics of both Uttar Pradesh and Uttarakhand for four decades.

Describing her death as a big loss for the state, Rawat remembered her for her profound knowledge of parliamentary procedures.

Rawat said it was also a personal loss for him as he always got the love and affection of an elder sister from her.

State government's spokesman and cabinet minister Subodh Uniyal said he and other politicians of his generation had learnt a lot from Hridayesh who could rise above the confines of party based politics.

"Her knowledge of parliamentary procedures was amazing. We learnt a lot from her," Uniyal said .

Pradesh Congress vice president Dhirendra Pratap described her as the "iron lady" of Uttarakhand.

Hridayesh was the Finance Minister of Uttarakhand from 2012 to 2017 and also held the portfolios of parliamentary affairs and higher education and planning in the Congress government led by Harish Rawat.