KIEV, Sept. 11 – President Viktor Yushchenko, citing a preliminary investigation, said undisclosed Ukrainian politicians probably played a role in his poisoning in September 2004, four months before he won the presidency.

“I am convinced that you will become aware of striking examples of the role and place of some politicians, including Ukrainian ones, concerning my poisoning,” Yushchenko said Tuesday. “Let investigators talk about that after getting all testimony.”

Yushchenko’s poisoning in 2004 caught headlines of international media and was cited as an example of pressure and intimidation on the opposition figure to prevent his election as president.

The investigation was making mixed progress, but it slowed down after Russia had refused to provide its samples of dioxin, a chemical substance that had been apparently used to poison Yushchenko.

Toxicology experts said three countries—the US, Britain and Russia--could actually produce the sophisticated brand of dioxin used to poison Yushchenko. The U.S. and Britain already provided their samples, which those hadn’t matched the dioxin found in Yushchenko’s blood.

The samples, once checked with those found in Yushchenko's body, could show exactly where the dioxin had been produced, and possibly help to trace down the shipment and those involved.

This highlighted speculations about possible role of Russia, which has been de-facto seeking to prevent the election of Yushchenko, a pro-Western leader, as the president in Ukraine.

Meanwhile, Russia has been continuing to hinder the investigation as three most wanted suspects are known to have been currently hiding out in Russia.

Seeking to speed up the investigation, Yushchenko asked Russian President Vladimir Putin for help. But the request has apparently fallen on deaf ears. “There is still no answer,” Yushchenko said.

Yushchenko first fell ill after having a dinner with Ukrainian Security Service chief Ihor Smeshko and his deputy, Volodymyr Satsyuk, on Sept. 5, 2004. He reported having a headache about three hours after the dinner, and by the next day had developed an acute stomach ache.

Yushchenko, who was rushed to a Vienna hospital on Sept. 10, later reported pancreatitis and gastrointestinal pain, as well as backache. He also suffered partial nerve paralysis in his face and an inflammation of one inner ear.

About three weeks after his first symptoms, he developed the rough, acne-like rash on his face which is the hallmark of dioxin poisoning.

Satsyuk, who hosted the dinner, later escaped to Russia, which has refused to extradite him. (jp/ez)