An unprecedented public grilling of the UK's key security and intelligence bodies has been postponed so MPs can concentrate on investigating state snooping allegations and the murder of soldier Lee Rigby, it has been announced.
The heads of the security service MI5, secret intelligence service MI6 and eavesdropping agency GCHQ had been due to appear before the Intelligence and Security Committee this month - the first time they would have been brought together in that way.
Chair Malcolm Rifkind had hailed it as an opportunity for the public to be assured that the agencies were using powers such as intercepting communications "appropriately" and providing value for money.
But it has now been postponed until September at the earliest with listening agency GCHQ under intense scrutiny over claims it sidestepped legal safeguards by accessing information about UK citizens gathered by the secret US Prism programme.
An apparent arrangement between the National Security Agency and GCHQ was among documents leaked by American whistleblower Edward Snowden - sparking a fierce debate on both sides of the Atlantic about the acceptable limits of state snooping.
They also appear to show that GCHQ is able to tap into fibre-optic cables carrying huge amounts of internet and communications data and store it for up to 30 days under an operation codenamed Tempora.
The agencies were handed a 3.4% budget boost in last week's spending review - to £1.7 billion in the financial year 2015/2016.
A committee spokesman said: "The Intelligence and Security Committee had intended to hold its first open evidence session in July.
"However the Committee is currently investigating both the murder of Drummer Lee Rigby and the allegations surrounding GCHQ as a result of material leaked by Edward Snowden, and these Inquiries must take precedence.
"The open evidence session has therefore been postponed until after the summer recess."
The international row over the reach of secret surveillance programmes was given fresh fuel at the weekend as European nations demanded an investigation into claims Washington bugged European Offices in the US.