Greenpeace International campaigner Aaron Gray-Block, says he has no idea why he was “blacklisted” and asked to leave the country immediately upon his arrival at Bengaluru airport, when all he planned to do here is meet the staffers of the India unit of the organization.Gray-Block arrived in India via Kuala Lumpur on Saturday night, but immigration officials said he could not enter the country and within hour, he was put in a flight back to Kuala Lumpur, from where he returned to Sydney.On Wednesday, The Times of India reported that 13 foreign nationals all but two of them from Greenpeace had been blacklisted.In an interview to The News Minute Gray-Block said he planned to stay in Bengaluru for three weeks as the largest number of Greenpeace staffers were located in the city and hold extensive meetings with.“I saw no reason why (the Indian government would be concerned) with our internal meetings. Greenpeace has been working in India for 14 years, and it seems like a clampdown by India on Greenpeace India by stealth,” Gray-Block said over the phone from Sydney.Gray-Block, who is a crisis response and media relations campaigner, said the meetings were to discuss issues of air pollution, climate change and coal mining, and exchange information with Greenpeace campaigners working on similar campaigns elsewhere. He said he did not have plans to travel within India.Gray-Block, a former journalist with Reuters in The Netherlands, says that he has travelled extensively in his three years with Greenpeace to places such as Japan, European countries, and even Russia, but has never experienced such treatment. He said he works on agricultural issues in central and east Asia, coal mining in Turkey and fishing. He said he acted as a facilitator who exchanging strategies and learning on issues.Asked why the meetings could not have been held through video conference, Gray-Block said a significant amount of discussions happened through email and Skype, but “face-to-face contact” was “irreplaceable”. Travelling to places to meet colleagues was sometimes necessary to get to know their talents and abilities was important, he added.“The issue is not whether I could have had meetings over video conference, but that my freedom of movement from one democratic country to another was denied. That’s a serious issue,” he said. He said that he was unaware that he had been blacklisted and that he had received no formal communication from Indian authorities.To the same question, climate and energy campaigher with Greenpeace India Vinutha Gopal said “There is a simple answer for that: the same time-zone. Not only are we in the same time-zone, but face-to-face meetings are the best form of communication.”She criticized the Indian government for impeding the “free exchange of people and ideas across the world”. She added that Greenpeace campaigns would continue as planned, that the organization is set to roll out campaigns for clean sustainable energy, air pollution, and solar power.