Washington ? AT&T faces a $780,000 fine for reaching out and touching consumers who had asked to be left alone, federal regulators said Monday.

The Federal Communications Commission said it was the first major penalty for violating do-not-call rules for telemarketers.

The FCC said AT&T made 78 phone calls to 29 consumers who had asked the company to leave them alone. The proposed fine is $10,000 per call.

“This puts telemarketers on notice that we will take all measures necessary to protect consumers who chose to be left alone in their homes,” FCC Chairman Michael Powell said.

The fine is based on alleged violations of FCC rules that require companies to maintain lists of people who have said they do not want to be called with sales pitches. It is separate from the do-not-call list maintained by the Federal Trade Commission, which allows consumers to put their numbers off-limits to a variety of companies.

AT&T spokesman Bob Nersesian said the company planned to respond to the complaint and had 30 days to answer it. The company issued a statement Monday saying it had not seen the specific allegations.

“We set a very high priority on respecting do-not-call requests and have even urged our customers to sign up for the FTC do-not-call list,” the statement said. “We want to stress that this FCC investigation is not based on the nationwide do-not-call list that went into effect in October.”

Consumer groups praised the FCC’s action.

“This is a clear signal to industry that they must take consumers seriously when consumers say they want to be left alone,” said Gene Kimmelman, senior policy director for Consumers Union, publisher of Consumer Reports.

Meanwhile, the FTC said Monday that the do-not-call registry now contained almost 54.3 million telephone numbers, and more than 51,000 complaints had been filed against telemarketers for allegedly calling numbers on the list. The agency is starting to investigate the complaints. Companies that repeatedly contact people who say they do not want to be called face fines of up to $11,000 for each violation.

The list, which took effect Oct. 1, is intended to block about 80 percent of telemarketing calls, with exemptions for charities, pollsters and calls on behalf of politicians. A company also may call people on the list if it recently has done business with them.

Telemarketers must obtain copies of the list every three months. To date, more than 33,000 companies have obtained lists of phone numbers, the FTC said.