Israel's Prime Minister Benjamin Netanyahu has reacted angrily to allegations that the United States spied on Israel's leaders. He said on Monday such activity was unacceptable and had no place in the allies' close relationship.
Documents leaked on Friday by former U.S. National Security Agency contractor Edward Snowden showed the NSA and its British counterpart GCHQ had in 2009 targeted an email address listed as belonging to then-Israeli Prime Minister Ehud Olmert and monitored emails of senior defence officials.
Mr Netanyahu did not elaborate on whether Israel intended to ask Washington for clarifications.
The revelation that Britain and America had a list of surveillance targets which included the Israeli Prime Minister, a European Union commissioner and various charities, has prompted an angry response.
The European Commission issued a statement saying the claims "deserve our strongest condemnation" if proved true.
"This is not the type of behaviour that we expect from strategic partners, let alone from our own member states," it said.
Unicef and Medecins du Monde were among the organisations listed in the latest batch of secret documents leaked by fugitive Edward Snowden to be published by the Guardian.
Leigh Daynes, an executive director of Medecins du Monde in the UK, told the Guardian he was "shocked and surprised by these appalling allegations of secret surveillance on our humanitarian operations".
Britain and America's intelligence services had a list of surveillance targets that included the office of the Israeli Prime Minister, German government buildings and a top European Union official, according to documents leaked by whistleblower Edward Snowden.
The documents, published by The Guardian, The New York Times and Der Spiegel, revealed that GCHQ and NSA had more than 1,000 surveillance targets in 60 different countries.
Foreign leaders including African heads of state and their family members, directors of the United Nations, officials overseeing oil and finance ministries all had their communications monitored by Britain and the US, according to the secret documents.
The documents chronicle NSA's and GCHQ's eavesdropping from 2008 to 2011.