WASHINGTON, June 6 (Reuters) - U.S. authorities conceded on Wednesday they made mistakes that worsened an international health alarm over an Atlanta lawyer who flew to and from Europe with a dangerous form of tuberculosis.

The actions by U.S. health and border security authorities in the case of Andrew Speaker drew criticism from lawmakers in two congressional hearings even as the 31-year-old man and health officials clashed over the facts of the case.

He said he was never told he posed a risk to others and that health officials with whom he met never wore protective masks. Health authorities said Speaker was told he had a hard-to-treat form of TB and was asked not to travel but then flew to Europe earlier than scheduled.

Speaker triggered the global health alert last month when he and his new bride flew around Europe and to Canada before driving back into the United States at a border crossing into New York state.

"We gave the patient the benefit of the doubt at several points here. In those cases, we failed to take the aggressive action that we could have used with legally sanctioned methods to restrict his movement more effectively," Dr. Julie Gerberding, director of the U.S. Centers for Disease Control and Prevention, told a Senate hearing.

"In retrospect, we wish we would have sent all kinds of alerts."

Speaker, testifying to a Senate panel by telephone from a Denver hospital where he is being treated, insisted he was never barred from traveling.

"I was repeatedly told that I was not contagious -- not that I was partly contagious but that I was not contagious, that I was not a threat to anyone," said Speaker, taking issue with Gerberding.

"Everyone knew I was going (to fly). I didn't go running off or hide from people. It's a complete fallacy and it's a lie," Speaker added.

CDC officials knew he was planning to travel to Italy and Greece for his marriage and honeymoon, and they knew he had a form of TB that was resistant to several drugs, he said.

NEW BORDER PROCEDURES

Customs and Border Protection Commissioner Ralph Basham said the agency had implemented new procedures to ensure people who were flagged to be stopped could not enter the country freely, as Speaker did. Basham did not detail the changes.

Basham said a single U.S. border agent erred in letting Speaker re-enter the country by ignoring an alert to detain him for medical reasons.

Gerberding called for clarification in the federal quarantine statute to allow authorities to prevent a patient from taking a health threat abroad rather than bringing one into the United States.

Dr. Steven Katkowsky, head of the health office in Georgia's Fulton County where Atlanta is situated, said state law did not give the office the power to block a patient such as Speaker from traveling.

"It looks like there was some bureaucratic mismanagement here," said Iowa Democratic Sen. Tom Harkin.

Speaker is being treated for extensively drug-resistant tuberculosis, or XDR TB, which is invulnerable to most antibiotics. He is not considered highly contagious, but health experts agree it may be possible for him to infect others.

Gerberding said CDC contacted Speaker in Rome, informed him of his diagnosis -- he previously had been told he had a drug resistant form but not XDR TB -- and instructed him not to fly on commercial airliners. But Speaker then traveled to Prague and took an airliner to Montreal.

REUTERS