The Conservatives are demanding a fresh Commons statement over the bugging of an MP which they say has made a "liar" of the Prime Minister Gordon Brown.
Sadiq Khan MP was bugged during a prison visit
It followed the revelation Home Office and Ministry of Justice officials were told about the incident in December.
Shadow home secretary David Davis said the case made the PM a "liar" as it countered prime ministerial pledges to protect MPs from bugging.
Commons leader Harriet Harman said Mr Davis should "apologise" to Mr Brown.
She told BBC Radio 4's World at One there was "no justification" for his accusation.
PM's promise 'broken'
It follows claims counter-terrorism officers secretly recorded discussions between Tooting MP Sadiq Khan, a government whip, and a constituent he was visiting in jail.
Justice Secretary Jack Straw and Home Secretary Jacqui Smith had not been aware of the incident until the Sunday Times reports emerged this weekend.
But the fact officials in their departments knew in December led Mr Davis to say the case raised questions over "who is in charge" of surveillance in the UK.
"Why was this allowed to happen without ministerial knowledge?" he said. "When it was discovered in December, they didn't tell Jack Straw or Jacqui Smith.
"These intercepts have broken a prime ministerial promise. They involve the intercept of the justice whip - someone who works with Mr Straw.
"This is a very serious issue. It's a breach of a prime ministerial undertaking to Parliament, so it makes the prime minister a liar, basically."
The conversations alleged to have been recorded took place in 2005 and 2006 at Woodhill Prison.
They were between Mr Khan and Babar Ahmad - a constituent and childhood friend - who is in prison awaiting extradition to the US.
He is accused there of running websites supporting the Taleban and Chechen terrorists, though he faces no charges in the UK.
A 40-year-old code known as the Wilson Doctrine forbids - or was thought to forbid - the covert recording of conversations between MPs and their constituents.
Mr Davis said: "It is beyond belief that the department would not flag up to a minister that the Wilson Doctrine had been broken within the department.
"It now appears that Mr Straw is in as little control of his department as the home secretary is of hers."
Lib Dem leader Nick Clegg said the incident was "the inevitable result of the government's continual erosion of individual liberty".
"Many of those MPs who have protested about the bugging of Mr Khan are the ones who supported the government's ID card scheme and the retention of the DNA of people who have never been charged with any crime."
Meanwhile, the ex-police officer who claims he bugged Mr Khan's visit to Mr Ahmad says his life is "at risk" after the case was leaked to the media.
Mark Kearney, a former police intelligence officer at Woodhill Prison in Milton Keynes, says he did not think it was right to bug Mr Khan.
May 2005 & June 2006:Sadiq Khan MP's visits to Babar Ahmad are recorded
December 2007:Home Office and Ministry of Justice officials informed of incident
11 December 2007:Letter sent by Tory David David to prime minister. No record of letter received
2nd February 2008:Jack Straw informed ahead of Sunday Times revealing details
But he claimed the Met Police put him under "significant pressure" to do so.
The former Thames Valley Police sergeant, who was working at the jail, faces charges - unrelated to the bugging claims - of leaking information to a local newspaper.
He told the BBC he was "shocked and disgusted" that the case had been leaked to the media.
"I believe it puts my life and safety at risk," he said. "I would also like to say I am quite prepared to cooperate with any inquiry so it can reach a proper conclusion."
Mr Straw announced on Monday that Chief Surveillance Commissioner Sir Christopher Rose is to head an inquiry into the allegations.
He said Sir Christopher, a former Court of Appeal judge, would try to find out under whose authority any bugging was carried out and would present his findings within two weeks.
Mr Straw insisted that a chief police officer had to authorise eavesdropping operations, adding that "ministers play no part in these authorisations".