Kiev, Ukraine ? Opposition leader Viktor Yushchenko starkly accused the government Thursday of poisoning him in a “political murder” to knock him out of the presidential race, saying his massive dioxin dose probably came from a dinner three months ago with Ukraine’s security chief.

In an interview with The Associated Press, Yushchenko laid the blame unequivocally on the government of President Leonid Kuchma and Prime Minister Viktor Yanukovych, his opponent in the contest to be decided in a Dec. 26 repeat of their fraud-marred runoff.

For the first time, he also pinpointed the time and place the poisoning likely took place: a Sept. 5 dinner with the head of the Ukrainian Security Service, Ihor Smeshko, and his deputy, Volodymyr Satsyuk.

“That was the only place where no one from my team was present and no precautions were taken concerning the food,” Yushchenko told the AP. “It was a project of political murder, prepared by the authorities.”

Yevhen Chervonenko, a lawmaker and the head of Yushchenko’s security detail, told the AP on Thursday that he had tasted all Yushchenko’s food that day except for what was served at the security service deputy’s dacha.

“The authorities did it because I am the opponent, the opposition candidate for Ukraine’s presidency,” he said. He said he was “very much in the way” of the leadership’s plans.

The two top security service leaders were unavailable for reaction to Yushchenko’s allegations, and a security service spokesman declined comment.

Earlier this month, as tens of thousands of his supporters took to the streets, Yushchenko won a Supreme Court decision throwing out the Ukraine election commission’s decision to award the Nov. 21 runoff to Yanukovych.

The opposition leader was lively and upbeat in the interview, his confident and jovial mood flashing through a face discolored and pockmarked from the second-highest level of dioxin poisoning ever recorded in a human being.

Yushchenko has suggested in the past that he was poisoned by Ukrainian authorities, but had not explicitly said so. Members of Yushchenko’s campaign team had spoken of the dinner as a possible source of the poisoning. His spokeswoman, Irina Herashchenko, has said that he met with the security chiefs to discuss the security agency’s meddling in the campaign.

Yanukovych, also interviewed by the AP on Thursday, responded to Yushchenko’s claim by saying that he had no link to any faction among the Ukrainian authorities that could have been behind the poisoning.

“‘The authorities’ is a very loose definition. That includes parliament, the judiciary, local authorities and of course, law enforcement agencies and the president of Ukraine, who heads the government,” he said.

“I don’t want to be associated with the part of the authorities that Yushchenko was talking about,” said Yanukovych.