Justice Secretary Jack Straw has appeared to indicate ministers had been "surprised" by the nature of the raids on Tory frontbencher Damian Green's homes and offices.
He said: "Everybody who has been made aware of these unfolding events of course is surprised by the nature of the raid, and I certainly understand the concern of my parliamentary colleagues."
Mr Straw, a former Home Secretary and former leader of the House of Commons, indicated that any future review into the raid on Mr Green's parliamentary office was a matter for the House of Commons, but added: "I am pretty certain...that it will be because of the extent of the concern."
Commons Speaker Michael Martin is under mounting pressure from MPs to explain why police were allowed to raid the Parliamentary office of Mr Green.
Amid speculation that anger could erupt into protest, the Speaker's office announced Mr Martin would make a statement on Wednesday when the House returned for the State Opening of the new session.
Politicians from all sides have condemned the police action - former Labour minister Denis MacShane dubbed it "a mammoth breach in the core democratic doctrine of parliamentary privilege".
A civil servant arrested over the alleged Home Office leaks passed information Mr Green in the belief it would be used "in a responsible manner in the public interest", his lawyer said.
Christopher Galley's solicitor Neil O'May was speaking at a press conference in London following Mr Green's arrest last week.
Mr O'May said his client was unable to speak as he is still under active police investigation and due to return to police in January.
But he added: "If ever there was a case of 'don't shoot the messenger', this is surely it."
