N E W Y O R K, July 24, 2002 -- The Rev. Al Sharpton says he plans to sue HBO for $500 million and pledges that his plans to explore a run for the White House would not be derailed by what he calls a "smear campaign."

His annnouncement came in response to cable channel HBO's airing of an 1983 FBI surveillance videotape that shows Sharpton talking with an undercover agent about a drug deal.

The tape, shot nearly 20 years ago, aired Tuesday evening on HBO. It was obtained for an episode of HBO's Real Sports with Bryant Gumbel that reported on possible ties between the sports world and organized crime.

The grainy, 90-second clip shows Sharpton listening as an undercover FBI agent proposes a drug deal. At one point on the tape, the agent is heard offering a 10 percent cut to Sharpton for finding a buyer.

"Every kilogram we bring in — $3,500 to you. How does that sound?" asks FBI Agent Vincent Quintana as Sharpton appears to nod. "So if we bring in 10, you'll make $35,000."

"I hear you," Sharpton responds.

"But that's a drip in the bucket," the agent adds.

"Well if [the buyer] can, if he's gonna do it, he'll do it much more than that," says Sharpton, who can be seen wearing a large cowboy hat while holding an unlit cigar in his mouth.

A Second Tape?

But Sharpton told ABCNEWS' Good Morning America that there is another tape that would erase any suspicions about his actions. He says he asked HBO to air that additional footage and criticized the network for not telling the whole story.

"If they [HBO] brought out all of the tapes, which the lawsuit will do — and you know there were tapes brought out 10 years ago — we wouldn't do anything," said Sharpton. He did not identify who possesses the second tape.

In a Tuesday press conference, Sharpton threatened to sue HBO for "knowingly omitting information that would clearly show what my character and activity was at that time."

During the HBO broadcast, reporter Bernard Goldberg denied there is "no tape or any other evidence" to support Sharpton's claims. And HBO spokesperson Ray Stallone said, "Our report speaks for itself."

Smear Campaign?

Sharpton says the tape was aired in an attempt, "to smear me as I try to raise issues in America that others aren't raising."

In his Tuesday press conference, Sharpton said he wouldn't let the broadcast interfere with his his "exploration to run for the president of the United States."

Sharpton says the FBI agent posed as a Latin American businessman and approached him to discuss promoting boxing matches and musical events back in 1983. When the man brought up drugs, Sharpton said he became frightened.

"I am in an office. I don't know if this guy has got a gun. I don't know if there are people between the offices," Sharpton said. "I am surprised at the turn of events."

HBO said it did not get the tape from the FBI. Bureau spokesman Joe Valiquette said Tuesday that to his knowledge the FBI had not released them.

A 1988 Newsday report, citing unidentified sources, said Sharpton became a federal informant when approached with the tape months after it was recorded.

But Sharpton denied that report on GMA today, adding that he plans to continue his efforts to rid neighborhoods of drugs and crack houses.