KIEV, September 23 (RIA Novosti) - An investigation commission of the Ukrainian parliament has demanded that the country's Prosecutor General's office launch a probe into falsification of President Viktor Yushchenko's dioxin poisoning, a Ukrainian on-line newspaper said.

The Ukrayinska Pravda (Ukrainian Truth) cited the commission's press service as saying it has enough evidence "supporting the fact that Yushchenko's blood samples were tampered with."

"The commission has evidence demanding an immediate investigation of the information pointing out at the fact that Viktor Yushchenko's blood samples were taken on several occasions to the United States where they were enriched with dioxin," the commission said in a statement.

The statement claims that Roman Zvarych, former Ukrainian justice minister and currently member of parliament, earlier confirmed in several interviews that he travelled to the U.S. with Yushchenko's blood samples.

Yushchenko fell ill shortly after a dinner on September 5, 2004 with the then security service head Ihor Smeshko, and his deputy, Volodymyr Satsiuk, whom he had invited to discuss the 2004 election campaign.

The next day, Ukrainian doctors diagnosed food poisoning, and four days later, as his condition failed to improve, Yushchenko was taken to the Rudolfinerhaus clinic in Vienna, which he left later in the month for the election campaign.

Medical experts involved, including from the U.S., Austria and Britain, were divided over the cause of his illness, but in late 2004 the Rudolfinerhaus clinic confirmed that he had been poisoned with dioxin.

The incident left Yushchenko's face disfigured, and a number of conflicting theories arose as to who might have poisoned him - or indeed if he even was poisoned.

The commission said it has an audio recording of a 2004 conversation in English between a Ukrainian woman named Marta and a certain Roman about the transportation of Yushchenko's blood samples from the U.S. to Austria.

According to the statement, the Forensics Institute in Odessa (Ukraine) has concluded that "the voice of the so called Marta is identical with the voice of president's wife Catherine Yushchenko [who is a U.S. citizen]."

Ukrayinska Pravda (Ukrainian Truth) is a popular Ukrainian on-line newspaper, founded by Georgiy Gongadze in April, 2000.

The newspaper is often first to investigate and publish the material on corruption or unethical conduct of or related to Ukrainian politicians from all political camps.