New Delhi, Jan 12 (ANI): Greenpeace India Senior Campaigner Priya Pillai was allegedly stopped at IGI Airport from boarding a flight to London. Pillai while speaking on the issue said that she was stopped at the immigration counter despite having a valid visa and her passport was stamped with "offloaded." She added that she was on her way to meet a group on tribal affairs and another on Indo-British relations and wasn supposed to talk on the Mahan coal block issue and its impact on tribals. She further stated that the whole process is a 'bullying tactic' by the government. Greenpeace India has written to MEA and Airport Authority of India about barring Pillai and has asked the government to explain the legal basis for the ban on her leaving the country.