US immigration authorities, in the past four years, have increased denial of work-related visas, with India-born professionals being refused at higher rates than nationals of other countries, an American think tank said in a report on Friday.

Analysis of new data obtained from US Citizenship and Immigration Services showed the agency had increased denials of L-1 and H-1B petitions beginning 2008, thus harming the competitiveness of US employers and encouraging companies to keep more jobs and resources outside the country, said the report released by the National Foundation for American Policy (NFAP).