Google and Microsoft's Bing have agreed to crack down on piracy sites in the UK after years of wrangling with film and music rights holders.

The tech giants have inked a voluntary code of practice with the British Phonographic Industry (BPI) and Motion Picture Association following a series of talks overseen by the UK's copyright watchdog and steered by the department for culture, media, and sport.

On Monday, the Intellectual Property Office described it as a "landmark agreement" in which Google and Bing have vowed to reduce "the visibility of infringing content in search results by 1 June 2017." It means that repeat offenders who post pirated material online will see their sites drop off the first page of Google and Bing when film and music fans search for content. Instead, searchers will apparently be shepherded towards legit sites.

Google—which commands more than 90 percent of the search market in Europe—was keen to play down the significance of the agreement. "Google has been an active partner for many years in the fight against piracy online," it said in a statement to Ars. "We remain committed to tackling this issue and look forward to further partnership with rights holders."

The BPI sees thing differently, though. It said that the new voluntary code represented a "first-of-its-kind initiative" to tackle illegal piracy. It added that action against copyright theft—such as court ordered site blocking—would continue in tandem with the measures that Google and Bing will bring in to demote the prominence of infringing sites.

"Pirate sites deprive artists and rights holders of hard-earned income and I’m delighted to see industry led solutions like this landmark agreement which will be instrumental in driving change," said digital minister Matt Hancock.

BPI chief Geoff Taylor admitted that the new arrangement "will not be a silver bullet fix, but it will mean that illegal sites are demoted more quickly from search results."

Last July, the IPO reported a conservative fall in online infringement due to a "steep rise" in consumers accessing video-streaming services. Nonetheless, it found that seven million Web users were still accessing illegal material in the UK.

Google's statement about "further partnership with rights holders" also points at the fact that it hopes to avoid regulatory meddling from the British government—which had threatened to bring in legislation if the relevant parties failed to strike a deal.

During the committee stage of the Digital Economy Bill earlier this month, Baroness Buscombe told the upper chamber:

"The search engines involved in this work have been very co-operative, making changes to their algorithms and processes, but also working bilaterally with creative industry representatives to explore the options for new interventions, and how existing processes might be streamlined. I understand that all parties are keen to finalise and sign up to the voluntary agreement, and so we believe there is no need to take a legislative power at this time.

"Surely it is better to act on a co-operative basis now, and start tackling this serious issue right away. If, however, a voluntary deal cannot be achieved, we will re-evaluate our options."

In the US, search engines have been under similar pressure within the last decade to make it harder for individuals seeking out piracy options. In 2012, Google famously pledged to "downrank sites for which we received a large number of valid DMCA [Digital Millennium Copyright Act] notices," but the Recording Industry Association of America soon conducted a study calling the solution ineffective. In 2014, Google tried again with a new anti-piracy algorithm that appeared to be more effective, dropping one of Project Free TV's main domains by 96 percent in search results, according to reports at the time.