Rajendra K Pachauri has quit as chairman of the UN's Intergovernmental Panel on Climate Change (IPCC) days after the police began investigating charges that he sexually harassed a 29-year-old woman employee in Delhi.
"The IPCC needs strong leadership and dedication of time...which under the current circumstances I may be unable to provide...," Dr Pachauri has said in a letter to UN Secretary General Ban Ki-Moon.
Dr Pachauri, 74, is one of the world's top climate change officials. A researcher at his Delhi-based The Energy and Resources Institute (TERI) claims the scientist began harassing her soon after she joined the non-profit think-tank in September 2013.
Dr Pachauri has denied the charges; today, he said in a letter to TERI that he was proceeding on leave to ensure the inquiry against him - which includes the questioning of those at his institute - is impartial.
The woman has submitted hundreds of text and WhatsApp messages that she says prove how she was sexually harassed; Mr Pachauri's lawyers have alleged that his computer and phone were hacked.
The case comes at a time when Dr Pachauri is playing a key role in the run-up to a crucial climate change summit in Paris in December where world leaders are expected to agree a new deal to curb global warming.
In 2007, the IPCC was jointly awarded the Nobel Peace Prize with former U.S. Vice President Al Gore for their part in galvanising international action against climate change.
The IPCC will elect a new chair at a session planned for October and Dr Pachauri, who was first elected as the panel's chair in 2002, will not stand for a third term.
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