New measures to prevent a repeat of the intelligence failings that preceded the Iraq war have been announced by Foreign Secretary Jack Straw.
The late Dr David Kelly criticised how intelligence was used
The move is a response to the Butler report which found much of the pre-war intelligence was unreliable.
The changes will tighten up government use of secret information.
The Lib Dems say the announcement highlights the issue of trust in the government. The Tories say the changes are too little too late.
Mr Straw said Lord Butler's report had made a great contribution to the future shape of intelligence services.
The government needed to move to implement the report's conclusions and it had done so "substantially", he said as he announced the reforms in a written statement to the House of Commons.
The secret intelligence service MI6 had developed new procedures and been given more cash to improve the evaluation of intelligence reports, he said.
The working methods of the Joint Intelligence Committee (JIC), which advises government on intelligence findings and produced the controversial dossier on Iraqi weapons of mass destruction, have been "reviewed and tightened up".
The prime minister has already agreed to appoint the next chairman of the JIC according to criteria laid down by Lord Butler, who said the chosen candidate should be "demonstrably free from influence".
This follows criticism of the promotion of John Scarlett, JIC chairman at the time of the Iraq dossier, to be head of MI6.
Less informal decision-making
More independent JIC
Views of government and intelligence staff clearly separated
New system for raising dissent
The government has also agreed to change Mr Blair's informal style of decision-making, which Lord Butler said reduced "the scope for informed collective political judgements".
"Where a small group is brought together to work on operational military planning and developing diplomatic strategy, in future such groups will operate formally as an ad hoc Cabinet Committee," the government said in Wednesday's statement.
The 28-strong Cabinet Office Assessments Staff, which analyses the work of intelligence services for ministers, will be increased so that reports can be more rigorously checked.
Ministers will also be given a confidential guidebook on how to assess secret information - including cautions on the limitations of intelligence material.
MI6 withdrew reports from three of its main sources on Iraq - including the source which claimed Iraq could deploy weapons of mass destruction within 45 minutes - because of their unreliability.
A Downing Street spokesman said the government had accepted Lord Butler's recommendations and was implementing them.
But shadow foreign secretary Michael Ancram said the reforms were "too little, too late" and accused Mr Blair of "seeking to avoid accountability" by not making the statement in person.
He claimed the prime minister had not given a "truthful account of the intelligence he received before going to war in Iraq" and accused him of then trying to blame the intelligence services.
"The sad fact is if we had to go to war again, the British people would find it hard to trust this prime minister."
Liberal Democrat foreign affairs spokesman Sir Menzies Campbell said: "Accepting Lord Butler's recommendations is one thing, but implementing them fully is another.
"Because of the restraints in the disclosure of intelligence, Parliament and the public have to rely on the competence of the people involved and the integrity of the system.
"These reforms will only be of any value if they enhance both of these."