The six largest Internet providers in the United Kingdom have agreed to send warning letters to customers who are believed to be illegally downloading and sharing music. 

From Reuters:

The music and film industries launched a fight back against online piracy on Thursday, persuading the six biggest Internet providers to send warning letters to those suspected of illegal file-sharing.

Some 6 million people are thought to engage in illegal file-sharing each year and the trend has cost the music and film industries millions in lost revenue.

ISPs had previously argued they were mere conduits and not responsible for content. But they agreed to the deal after the government said it would impose legislation if they did not work to curb illegal file-sharing.

Analysts said the plan would likely scare off younger users of illegal sites, who download content often without their parent’s knowledge, but would need to be just the first step in an escalating battle.