A Home Office advertising campaign that highlights one of Labour's key election policies on crime and policing is to be banned by the advertising industry watchdog, the Guardian has learned.

The Advertising Standards Authority has told the Home Office that its television adverts highlighting the government's "policing pledge" that neighbourhood officers can now be expected to spend 80% of their time on the beat is to be banned with immediate effect.

The ASA says in an adjudication to be published next week that the television ad breaches its "legal, decent, honest, truthful" code because it is misleading on at least three counts.

"The ad must not be broadcast again in its current form. We told the Home Office to ensure the basis of claims was made clear in future. We also told them to ensure they held adequate substantiation for future claims," says the final ASA adjudication, leaked to the Guardian.

The decision is embarrassing to Gordon Brown and the home secretary, Alan Johnson, who highlighted the neighbourhood policing pledge this month which was central to Labour's crime and justice policy in the coming election campaign. Labour has already issued a campaign video in effect accusing the Tories of being the "burglar's friend" for opposing the retention of DNA profiles of innocent people and the extension of CCTV coverage.

The ASA said the ad was misleading because while it said that 80% of officers' time would be spent "on the beat", it did not make it clear this included duties other than patrolling the streets.

It also said the ad did not make it sufficiently clear that the pledge doesn't apply to all 140,000 police officers in England and Wales, but only the 13,500 neighbourhood constables and 16,000 community support officers in neighbourhood policing teams.

The watchdog is also concerned that the advertised standard for time on the beat is not actually being met and "[the advert] does not make clear the commitment would not necessarily be delivered".

The ban follows a decision by the UK Statistics Authority to censure the Conservatives for their "misleading" use of violent crime statistics, raising the prospect that law and order will become one of the most disputed battlegrounds in the coming campaign.

The banned film is part of a Home Office campaign of TV, radio, press and online adverts launched last November to highlight the policing pledge, which makes clear what the public can expect from the police. The offending promise was also included in a leaflet delivered to more than 6 million households in 60 areas across the country.

Chief constables across England and Wales signed up to the pledge in December 2008 which committed them to a national minimum standard of policing for the first time, including the promise that neighbourhood police officers would spend 80% of their time on the beat.

The watchdog launched its investigation after two viewers made official complaints, challenging whether the 80% claim could be substantiated and claiming it was misleading. The Home Office told them that the pledge actually committed neighbourhood policing teams, but not all frontline police officers, to spending 80% of their time "visibly working in neighbourhoods. That included, for example, public meetings and school visits as well as patrolling the streets."

Although all 43 forces in England and Wales signed up more than 15 months ago to the pledge, the latest report by Her Majesty's Inspector of Constabulary, published five months ago, showed that 35 were falling short of the required standard. Some forces are not even monitoring the amount of time officers spend "working visibly" in their neighbourhoods.

The policing pledge was billed as the most radical reform from the government's shake-up of policing, and is supposed to entitle the public to a consistent national minimum standard of service from the police – including response times to 999 calls. The ad campaign also focused on a promise that the public can make an appointment to see the local police at a time that suits them within 48 hours about a non-emergency problem.

The Home Office has stated that "as of January 2009 is being delivered by all 43 police forces".

Polling published at the same time that the advertising campaign was launched showed that only 3% of people think that their local police spend 75% of their time on the beat in their area.

Gordon Brown, in his crime speech earlier this month, set out what he described as "new neighbourhood policing strategy" which includes the pledge for neighbourhood police to spend 80% of their time on the beat, a response to non-emergency issues within 24 hours and a public right to monthly beat meetings to discuss priorities.

A Home Office spokesperson said: "We are extremely disappointed by the ASA's decision as the advert was approved by the recognised body prior to its broadcast. We believe that 'on the beat' is a recognised term for what the police do whilst working in neighbourhoods and engaging with communities. This can be patrolling, talking to the public in the street, attending a residents' meeting, challenging people's actions and of course, where necessary, making arrests. We also believe that the adverts made it explicitly clear in the voiceover that it was neighbourhood policing teams who would be on the beat."

"We believe it is important to inform the public that they have a right to expect these national minimum standards, which is why we launched an advertising campaign to highlight these promises. Unless the public know what they have been promised, they cannot then hold their local forces to account if they fail to achieve the standard."