"Progress is neither fast, nor significant, enough," Paul Bainsfair, the director-general of the IPA, said in the letter, which has been sent to Google’s UK managing director, Ronan Harris, and Facebook’s regional director of northern Europe, Steve Hatch.
The IPA, the trade body for UK agencies, which gave a copy of the letter to Campaign, said Google and Facebook have "a responsibility" as the two biggest digital media owners, particularly in video.
The UK could be a "test bed" for Google and Facebook to introduce "global gold standards" that they could then use in other markets around the world, Bainsfair said.
"While we acknowledge that small steps towards addressing recent concerns have been taken, our advertisers and agencies are increasingly telling us that this progress is neither fast, nor significant, enough," he wrote.
"We believe it is incumbent upon the key players in this sector, therefore, to show real commitment to finding solutions to these problems."
The IPA’s decision to publicise the letter is unusual and suggests it has lost patience with Google and Facebook and wants to pressurise them, following recent problems involving extremist content on YouTube and measurement errors on Facebook.
The letter (below) calls on YouTube and Facebook to sign up to a UK cross-industry initiative, called the Jicwebs Digital Trading Standards Group’s good practice principles, to improve brand safety.
Media owners and tech companies that sign up to the DTSG principles allow independent verification of their brand safety policies by an independent body such as the Audit Bureau of Circulation.
Google’s Double Click has signed up to DTSG principles, but YouTube and Facebook have yet to do so.
The IPA’s letter also urges Google and Facebook to allow independent verification of video viewability and video audience measurement.
Both Google and Facebook have said previously that they want to tackle problems with the digital media supply chain and have tightened up their policies.
However, they have been reluctant to allow independent, third-party measurement, despite making some concessions.
A Facebook spokesman said: "We are already engaged in a constructive dialogue with the IPA and its members on these important topics. We take our commitment to advertisers seriously, and through continued investment and innovation we're making progress, together with our partners in the industry.
"In the last few months we've announced an extra 3,000 content reviewers to nearly double our existing team, as well as new buying options and controls for advertisers that give choice and transparency over how and where ads appear on the platform. We have also updated our metrics to give more clarity and confidence about the insights we provide, including our work with 24 third-party measurement partners who can verify the value we drive for advertisers."
Google declined to comment, but stressed it wants to maintain good relations with the IPA.
A source who is close to Google said it has acknowledged that it has got some things wrong on brand safety and introduced additional controls and it said it has also allowed third parties to monitor viewability and measurement.
Another person, who is close to one of the tech companies, expressed surprise that the IPA has chosen to write to Google and Facebook in this way and to publicise the letter.
Edited version of IPA director-general Paul Bainfair’s letter to Google and Facebook in the UK:
I am writing today to ask for your urgent action on a number of key points.
As you are well aware, online budgets have exploded from around 16% of total spend (2007) to over 40% today. The internet has evolved into a complex ecosystem with online video now established as an important component of internet time. YouTube and Facebook being the two biggest channels.
The IPA and ISBA represent the UK’s biggest advertising agencies and advertisers and in our judgement urgent action is needed to bring the safety, measurement and viewability of your online video up to acceptable industry standards.
The purpose of this letter is to formally call upon Facebook and Google YouTube to work with us to deliver global gold standards in online advertising verification and cross-platform video advertising audience measurement.
We want you to use the UK as one of the largest, most advanced and concentrated digital media markets in the world as a test bed to drive best in class verification and measurement for brand advertising.
And we are calling for you to make the following action points.
The UK has the most robust online brand safety initiative in the world in the form of the Jicwebs DTSG. And yet it has also witnessed the most damaging press coverage for brands in light of this subject.
We are calling upon Facebook and YouTube to become signatories to the DTSG Good Practice Principles which will entail the independent verification of their brand safety policies and processes within six months.
Video audience measurement
Recently published evidence derived from the Databank of IPA Effectiveness Awards concludes video advertising, both on and offline, to be the most effective brand-building form.
We are calling upon Facebook and YouTube to meet standards of independent industry-owned audience measurement such that cross platform video audience measurement can be achieved.
The basis of video advertising brand building is that the advertisement is viewable by a human. The greatest growth rate of video viewership is on mobile, dominated by two businesses.
We are calling upon Facebook and YouTube to use the UK as a test bed for delivering online and mobile video ad supply that is optimised for 100% viewability and which can be independently verified.
As to next steps, we would be very happy to meet with you both individually, or together to discuss how we can progress these points and look forward to your constructive and speedy response.
I cannot emphasise enough, the importance of this request.