In 2008, of the more than 3.6 million foreigners coming to the US on resident non-immigrant visas, Mexico topped the list with 440,099 followed by a close India with 425,826 admissions.

Japan has been posted as a distant second with 257,401 admissions followed South Korea (216,648), Britain (216,280) and China (163,433), the report said.

The Annual Flow Report released by the Office of Immigration Statistics is based on the information gathered from the I-94 on the number and characteristics of non-immigrant admissions to the US in 2008.

"The leading countries of citizenship for resident non-immigrant admissions to the United States in 2008 were Mexico (12 per cent), India (12 per cent), Japan (7 per cent), South Korea (5.9 per cent), and the UK (5.9 per cent).

"These five countries accounted for more than 40 per cent of resident non-immigrant admissions to the US," it said.