Newly disclosed documents provided by whistleblower Edward Snowden have revealed the extent of the role the US government plays in directly enabling military assaults by Israel on Gaza.

The documents, published by investigative news outlet The Intercept, outline the relationship between the US National Security Agency (NSA) and the Israeli SIGINT National Unit (ISNU), and also expose the significant levels of money, arms and surveillance provided by the US government.

"NSA maintains a far-reaching technical and analytic relationship with the ISNU sharing information on access, intercept, targeting, language, analysis and reporting," state the documents, dated 19 April 2013.

"This SIGINT relationship has increasingly been the catalyst for a broader intelligence relationship between the United States and Israel. Significant changes in the way NSA and ISNU have traditionally approached SIGINT have prompted an expansion to include other Israeli and US intelligence organisations such as CIA, Mossad, and Special Operation Division (SOD)."

These revelations are at direct odds with the long-established US stance that it plays no greater role than that of a concerned bystander in the ongoing conflict between Israel and Palestine.

In a press conference last week, President Obama said: "I want to see everything possible done to make sure that Palestinian civilians are not being killed, and it is heartbreaking to see what's happening there."

'Constant, lavish support'

Formal ties between the NSA and ISNU date as far back as 1968, when an intelligence-sharing agreement was reached by US President Lyndon Johnson and Israeli Prime Minister Levi Eshkol. However, cooperation between the two has grown significantly in recent years.

Glenn Greenwald, editor of the Intercept and confidante of Snowden, believes that the relationship is crucial to enabling the current Israeli airstrikes on Gaza.

"The new Snowden documents illustrate a crucial fact," Greenwald wrote in an article accompanying the documents. "Israeli aggression would be impossible without the constant, lavish support and protection of the US government, which is anything but a neutral, peace-brokering party in these attacks."

One illustration of this support provided by the documents is that of the NSA's provisions to counter "Palestinian terrorism".

The documents state: "The Israeli side enjoys the benefits of expanded geographic access to world-class NSA cryptanalytic and SIGINT engineering expertise, and also gains controlled access to advanced US technology and equipment via accomodation buys and foreign military sales."