NEW DELHI: RK Pachauri , 79, founder director of New Delhi-based think tank The Energy and Resources Institute (Teri) and former chairman of the UN's Intergovernmental Panel on Climate Change (IPCC), passed away on Thursday.

He was battling cardiac ailments and was put on life support in a Delhi hospital on Tuesday. He had undergone open heart surgery at Fortis Escorts Heart Institute after suffering a stroke in Mexico in July last year.

Under his leadership, IPCC got the Nobel Peace Prize jointly with former US vice-president Al Gore. The prize recognised IPCC for its "efforts to build and disseminate greater knowledge about man-made climate change, and to lay the foundations for measures needed to counteract such change." He headed the body from 2002 to 2015.

Pachauri resigned from Teri in 2015 in the wake of allegations of sexual harassment.

Pachauri had multiple cardiac issues and doctors at Fortis Escorts Heart Institute said he had been put on life support three days ago. "Pachauri had also undergone an open heart surgery but his condition didn't improve," said a source, adding that Pachauri was taken home around 7pm on Thursday, where he breathed his last.

Pachauri became chief executive of Teri in 1981 and headed the institute for more than three decades. He had to quit his post of executive vice-chairman in 2015 in the wake of allegations of sexual harassment, stalking and criminal intimidation. In October 2018, a Delhi court had framed molestation charges against Pachauri, who had denied the charges. The court had given him anticipatory bail in 2015.

"Teri is what it is because of Pachauri's untiring perseverance. He played a pivotal role in growing this institution, and making it a premier global organisation in the sustainability space," said Ajay Mathur, director general, Teri, who succeeded Pachauri in 2015.

Pachauri was honoured with Padma Bhushan in 2001 and Padma Vibhushan in 2008.

"Pachauri's contribution to global sustainable development is unparalleled. His leadership of the IPCC laid the ground for climate change conversations today," Teri chairman Nitin Desai said.

An alumnus of the Indian Railways Institute of Mechanical and Electrical Engineering in Jamalpur, Bihar, Pachauri served in various positions in the Indian Railways, including at the Diesel Locomotive Works in Varanasi.

He had served in several organisations in different positions before founding Teri.

