NEW DELHI (AFP) - India summoned the top diplomat from the US embassy Wednesday to complain for the third time about spying following new allegations that the National Security Agency targeted the ruling party.

"What we have said is that we expect a response and an assurance that this won't happen again," a foreign ministry source told AFP on condition of anonymity.

A new document supplied by fugitive former intelligence worker Edward Snowden and made public by The Washington Post on Monday showed that Prime Minister Narendra Modi's Bharatiya Janata Party was among authorised targets for the NSA in 2010 while it was India's main opposition.

India has complained to the United States on two other occasions, in July and November 2013, over other revelations - including the disclosure that its UN mission in New York and its Washington embassy were snooped on.

Both times Washington has said it would look into what it can share about its espionage programme but failed to offer any details, the source said.

"We have said that we would like a response, which we haven't received," he said.

The new incident comes ahead of a visit to New Delhi by US Secretary of State John Kerry, who is expected to meet members of Modi's government in the next few months.

Modi, whose party swept to power in May with the first majority in 30 years, will travel to the United States in September for the UN General Assembly and his first meeting with President Barack Obama.

The US embassy is currently between ambassadors, meaning acting ambassador Kathleen Stephens is the most senior diplomat in the mission.

"As is standard, the US does not comment on its bilateral diplomatic communications with a host government," an embassy spokesman told AFP.