Government officials cleared the speech by Britain's top counter-terrorism officer that warned that budget cuts could imperil national security.

The revelation raises questions about a senior government minister's angry and direct attack on John Yates, Scotland Yard's counter- terrorism chief.

On Thursday Yates told a private gathering of police chiefs "eyewatering" cuts of £150m to the budget to fight terrorism would endanger the public, triggering a political row after his claim was leaked.

That led Cabinet Office minister Francis Maude to slap down Yates, saying that public servants had to be "damn sure" they had cut out waste, warning they should avoid "shroud waving" and claims of dire consequences that would "alarm the public". Former Labour home secretary Alan Johnson backed the top officer's assessment.

Yates was speaking at a private session of top officers and police authorities at the Association of Chief Police Officers' conference.

Home Office officials saw Yates's speech before it was delivered, and raised no objections. The procedure was standard because a top Whitehall counter-terrorism official was also due to address the private session, but had to cancel.

More details emerged of Yates's speech. Sources told the Guardian that Yates had said the cuts would mean the public and government would have to "accept a higher level of risk" of a terrorist attack.

Yates also said the threat of an al-Qaida inspired attack remained severe, with extremists having plotted to attack a prominent individual within the last two months, in a change of terrorist tactics.

Yates told the meeting his warning was "not shroud waving" but that he, regional counter terrorism squads plus the police authorities who fund them have to face the full reality of what the cuts could mean. Delegates heard that officers seconded to counter terrorism face being sent back to their home forces, who would have to deal with the extra costs of their return.

Later, at an open session at the Acpo conference Yates, despite several opportunities, did not repeat his private warning about the potentially dangerous effect of the cuts. But in a BBC interview Maude attacked the officer's remarks. It was a rare assault by a minister on a serving senior police officer.

Maude said: "The obligation that rests on all of us is to make damn sure that we take the cost out to the maximum extent possible out of our internal processes, [and] not alarm the public with that kind of talk."

"I'd like to avoid public servants doing this kind of shroud waving in public. There is a special responsibility on all public servants to be really careful what we say and what we do.

"It's going to be pretty important for people who are managing big public services like police forces to focus on cutting out unnecessary costs, driving down costs, being as efficient as they possibly can before they even begin to contemplate talking about alarming the public in this kind of way."

Johnson said the government's failure to ring fence budgets for policing and counter terrorism would "seriously affect" the fight to thwart al-Qaida attacks on Britain.

Scotland Yard's counter-terrorism unit has already suffered a £5m cut this year with another an estimated £87m to come in the next four years, with regional counter-terrorism squads facing a £62m cut in the next four years.

The total counter-terrorism budget is £600m and some in the police believe it is too well resourced given the cuts facing the service overall. Yates is no stranger to the anger of politicians. He was criticised by Labour when he led the cash-for-peerages investigation.

At an open session Yates made his case as to why counter-terrorism was a special case when questioned by a senior colleague. Yates said that while areas such as fighting serious and organised crime were about reducing harm, he said "counter-terrorism is about zero tolerance," a reference to the fact that police feel the public and government demand a "100% success rate" in stopping attempts by terrorists to cause mass murder on British soil.

This Wednesday sees the fifth anniversary of the 7 July terrorist attacks on London in 2005, which killed 52 people and injured 750.

Scotland Yard declined to comment.

The Home Office said: "National security is the first duty of government."Future police grants will not be set until later this year after the Spending Review."