India today summoned a senior US diplomat in New Delhi and registered its protest over reports that US' National Security Agency, NSA, had sought and obtained legal authorisation to spy BJP in 2010.

Official sources said New Delhi sought assurance from the US that it will not happen again and termed the act as unacceptable. The snooping case came to light after revelations by former NSA contractor Edward Snowden.

Quoting a document made public on Monday, a US newspaper wrote that BJP figures in the list of foreign political parties along with Lebanon's Amal, Egypt's Muslim Brotherhood and the Pakistan People's Party on whom NSA was given permission to carry out surveillance. It is, however, not clear if NSA did snoop the BJP.

Yesterday, External Affairs Ministry spokesperson Syed Akbaruddin had termed as extremely disconcerting the reports that the ruling-BJP was spied upon by NSA. He said it was totally unacceptable that an Indian organisation or Indian individual's privacy was transgressed upon.