Theresa May is facing calls to return to the drawing board on new spying laws after a third inquiry called for major changes to the "flawed" proposals.
The Home Secretary was warned the Government has not yet made a conclusive case for new powers to compel internet firms to store records relating to people's web and social media use.
It came as a group of MPs and peers became the third parliamentary committee to call for substantial revisions to the draft Investigatory Powers Bill in less than a fortnight.
Unveiled by the Government last year, the proposals are an attempt to bring surveillance tactics used by police and intelligence agencies in the digital age under one legal umbrella.
The Joint Committee on the Draft Investigatory Powers Bill said the Bill needs "significant amendments" and made 86 detailed recommendations.
Lord Murphy of Torfaen, chairman of the committee, said there is "much to be commended" in the Bill but added: "The fact that we've made 86 recommendations means that we think part of it was flawed and part of it needs to be looked at in greater detail. There is a lot of room for improvement."
Earlier this month, a report by the Commons Science and Technology Committee said aspects of the Bill are confusing.
Then on Tuesday the Intelligence and Security Committee said it was unclear, lacks sufficient privacy protections and fails to cover all the intrusive powers used by spy agencies.
The latest report said the Home Office has "further work to do" on plans to require communications service providers to collect and store data known as internet connection records (ICRs).
ICRs detail services a device connects to but not users' full browsing history or the content of a communication.
The committee said it was satisfied the potential value of ICRs "could outweigh the intrusiveness involved in collecting and using them" but it had heard "strong concerns" about a "lack of clarity" over what form they would take.
It added that it "has not been persuaded that enough work has been done to conclusively prove the case" for ICRs.
It also found that:
::Fuller justifications are needed for bulk powers that allow security services to collect large volumes of data.
::The Bill should be amended to clarify that the approach to encryption is not designed to compromise security or require the creation of "back doors" for authorities.
::The Government needs to make it explicit that firms offering "end to end" encryption on services will not be expected to provide decrypted copies of those communications "if it is not practicable for them to do so".
The report made a number of recommendations on the proposed new oversight system, which will see judges given greater involvement in the authorisation of security services' most intrusive powers.
It welcomed the creation of judicial commissioners but said they should have the power to instigate investigation on their own initiative and a legal mandate to access all relevant technical systems to "ensure effective oversight".
Rachel Logan, of Amnesty UK, said the Bill had been subject to a "tsunami of criticism", adding: "It's clear the Home Office needs to go back to the drawing board."
Shami Chakrabarti, director of Liberty, said: "The Government needs to pause, take stock and redraft – to do anything else would show astonishing contempt for parliamentarians' concerns and our national security."
Liberal Democrat Home Affairs spokesman Alistair Carmichael said: "If the draft bill is left in anything like its current form it will have a very rough ride ahead of it through Parliament."
Mrs May said the Government will "carefully consider" the conclusions of the three committees before presenting its final proposals.
She said: "This is vital legislation, and we are absolutely determined to get it right.
"Our draft Bill followed three independent reports on investigatory powers, whose authors were unanimous a new law was necessary.
"We are clear we need to introduce legislation which responds to the threats we face in the digital age, protects both the privacy and security of the public, and provides world-leading oversight and safeguards."
In a letter to Mrs May, Labour's Andy Burnham and Sir Keir Starmer wrote: "It is our view that the Government must now take time to reconsider the draft Bill, taking into account the conclusions and recommendations in the three detailed reports, and return to Parliament with a significantly revised and improved Bill."