Prime Minister David Cameron yesterday faced calls to address parliament on why Britain's top civil servant pressured The Guardian newspaper to destroy or return Edward Snowden's leaked files.
The call from a senior lawmaker came as Deputy Prime Minister Nick Clegg's spokesman said that asking the left-leaning daily to comply was better than taking legal action over the secret documents handed over by the former US National Security Agency (NSA) contractor.
Two months ago, Cabinet Secretary Jeremy Heywood, Britain's top civil servant, issued the newspaper with the ultimatum to return or destroy the material, or face court action, it emerged on Tuesday.
Politically neutral, Heywood is Cameron's most senior policy adviser and sits beside him at the cabinet table in Downing Street.
"If highly sensitive information was being held unsecurely, the government would have a responsibility to secure it," a Downing Street spokesman said.
Keith Vaz, chairman of the House of Commons' Home Affairs Select Committee, called on Cameron to make a "full statement" to the chamber when MPs return on October 8.
A spokesman for Clegg said the deputy PM understood concerns about press freedom and civil liberties. But he "thought it was reasonable for the cabinet secretary to request that The Guardian destroyed data that would represent a serious threat to national security if it was to fall into the wrong hands," the spokesman said.
Meanwhile the detention of David Miranda, 28, and the confiscation of his mobile phone, laptop and other equipment has caused an international outcry and sparked protests from Brazil.
Miranda is the partner of Guardian journalist Glenn Greenwald, who covered stories based on leaks by Snowden.
The Brazilian's lawyers are challenging the legality of his detention at Heathrow Airport under antiterror laws.