The green body said that Chellam will anchor the NGO which has been "facing a series of challenges from a number of government agencies apart from renewing the organisation's focus on campaigns for a clean and safe future".
This comes after former Executive Director Samit Aich had resigned in June last year following an internal review of the organisation's handling of two sexual harassment cases. Programme Director, Divya Raghunandan, too had quit at the same time.
The government had earlier barred Greenpeace India from receiving foreign funds by suspending its licence for six months and freezing all its accounts after alleging that it has "prejudicially" affected the country's interests.
"We are at a critical juncture in human history and as we saw at the recent climate talks in Paris, India has a tremendous opportunity to lead meaningful change at a global level....
"Over the last year, Greenpeace India has had to defend itself against a barrage of charges, but has drawn strength from the thousands of Indians who join in our campaigns, and the judiciary which has upheld our position time and time again," Chellam said in a statement.