Mrs Tripp, whose tapes led to the impeachment of President Clinton over his affair with Ms Lewinsky, was charged with breaking wiretapping laws in the state of Maryland.

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Mrs Tripp is the only central figure in the Lewinsky scandal facing criminal charges.

The president was acquitted in a Senate impeachment trial on charges of perjury and obstruction.

Mrs Tripp handed her tapes over to Special Prosecutor Kenneth Starr, giving him valuable ammunition for his investigations into the president's activities.

She secured a federal grant of immunity from prosecution, but this does not apply in a state case.

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Maryland State Prosecutor Stephen Montanarelli said the grand jury indicted Mrs Tripp on one count of illegal interception of a phone conversation on 22 December 1997, after she had allegedly been told by her lawyer that the taping was illegal.

The other count was for allegedly disclosing the contents of that conversation to Newsweek magazine. Under Maryland law telephone conversations may not be intercepted without the other party's consent.

Wiretapping is punishable by up to five years in prison and a $10,000 fine for each offence.