US intelligence services are spying on the European Union mission in New York and its embassy in Washington, according to the latest top secret US National Security Agency documents leaked by the whistleblower Edward Snowden.

One document lists 38 embassies and missions, describing them as "targets". It details an extraordinary range of spying methods used against each target, from bugs implanted in electronic communications gear to taps into cables to the collection of transmissions with specialised antennae.

Along with traditional ideological adversaries and sensitive Middle Eastern countries, the list of targets includes the EU missions and the French, Italian and Greek embassies, as well as a number of other American allies, including Japan, Mexico, South Korea, India and Turkey.