"The information announced by the prosecutor general at a briefing on September 20, alleging that NABU was engaged in unauthorized tapping of more than 150 people, including the presidential guards, is untrue," NABU said in a statement on Facebook on the same day.
"It is difficult to understand the causes why Yuriy Lutsenko has knowingly mislead the public. We do not exclude that such statements are intended to block the creation of an independent anti-corruption court and discredit the National Anti-Corruption Bureau in the eyes of the public and foreign partners," it said.
Read alsoDeputy Head of NBU complains over wiretapping, leaksNABU stresses that it has no authority to eavesdrop on their own and uses the means of the Security Service of Ukraine for this purpose.
Earlier on Wednesday, Prosecutor General Yuriy Lutsenko announced he had evidence that NABU agents had unlawfully wiretapped over 140 Ukrainian officials.
"I have legal evidence that NABU, having received permission to tap 18 individuals, had listened to talks of over 140 people. These are people from the Ukrainian president's security staff and other officials from different branches of power," Lutsenko said, adding that he had already reported this to NABU's chief. Results in this matter are expected in a few months, he said.
Commenting on the statement, NABU said: "The prosecutor general should have known it is technically impossible to replace one number whose wiretapping was authorized by a court with another."
"Even the very idea that the prosecutor general could have had evidence of illegal activity of a law-enforcement agency and had not taken measures to stop it, which could be qualified as crime of professional misconduct, is inadmissible," NABU added.