(Reuters) – August 19, 2008 -- The agency that brought you the "do not call" registry -- thus bringing a measure of peace to American dinner tables -- has now decided to tighten rules restricting prerecorded telephone sales calls.

It all started with the telemarketing industry, which uses automatic dialers that shunt calls to sales people. The industry asked the Federal Trade Commission to allow them to play a prerecorded message if a live sales agent was not available.

The FTC considered the change, said Allen Hile, assistant director for the division of marketing practices.

"We got a tidal wave of comments of people saying 'Are you nuts?"' Hile said in a telephone interview with Reuters on Tuesday.

The result is a rule that requires telemarketers with prerecorded calls to give consumers a way to opt out, the same way that they can now ask live sales agents to refrain from calling again. This goes into effect on December 1.

And, as of September 1, 2009, the telemarketer must have consumers' written consent to telephone them at all.

The commission's wildly popular "do not call" registry, which was signed into law in 2003, allows people to put their telephone numbers on a list of numbers that telemarketers are barred from contacting.