Britain's deputy prime minister called for urgent checks to see if the arrest last weekend of a journalist's partner under anti-terrorism laws was legal, distancing himself from his coalition partners who defended the nine-hour detention.
Nick Clegg said he was not consulted before the detention of David Miranda, the partner of American journalist Glenn Greenwald, who led coverage of former National Security Agency contractor Edward Snowden's leaks about US and British electronic spying.
Clegg's Liberal Democrats have held fast to Prime Minister David Cameron's Conservatives in vital areas such as economic policy but they disagree over issues ranging from Britain's role in Europe and its nuclear deterrent.
Writing in The Guardian newspaper, Clegg said he was not consulted before Miranda was detained under Schedule 7 of Britain's Terrorism Act.
"I acknowledge the many concerns raised about the use of Schedule 7 of the Terrorism Act 2000 for these purposes," he wrote. "It is immensely important that the independent reviewer of terrorism powers, David Anderson QC, reports rapidly on whether this was a legitimate use of the Terrorism Act, and whether that legislation should be adjusted."
David Anderson, a lawyer who acts as Britain's Independent Reviewer of Terrorism Legislation, wrote to Home Secretary May on Thursday to say he would investigate whether the powers under which police detained Miranda were used lawfully.
The Guardian meanwhile has agreed to give The New York Times access to classified documents leaked by Snowden.
In a brief story posted on its website, The Guardian said it "struck a partnership" with the Times after the British government threatened it with legal action unless it either surrendered or destroyed files it received from Snowden about Government Communications Headquarters - Britain's equivalent of the NSA.
The Times' executive editor, Jill Abramson said: "We don't usually comment on our reporting before publication, but in this case we will make an exception since it is already public.
" The Times is reporting on material from The Guardian as well as other matters related to Edward Snowden."
Snowden, who has obtained asylum in Russia, was aware of the deal.
The website Buzzfeed reported that Scott Shane, a Times reporter who covers national security and intelligence matters, was working on stories expected to be published next month.
Associated Press, Reuters