“This case has all the circumstances giving us legal reasons to close the investigation,” Pshonka told a news conference in Kiev, RIA Novosti reported.
He said the case had not been terminated yet only because Yushchenko had continually refused to give blood tests and offered little cooperation in the official investigation.
“For the sake of history, so that the closing verdict is unbiased, it is desirable that Yushchenko give his blood sample,” Pshonka said.
Yushchenko poisoning theory was officially supported by Ukrainian authorities during his presidency from January 2005 until February 2010.
However, a new team of investigators assigned to the case after Yushchenko lost power alleged that the Yushchenko dioxin poisoning could have been falsified to strengthen his positions during 2004 presidential elections.
Investigators demanded that the ex-president give new blood tests, as traces of dioxin remain in blood forever.
Yushchenko, whose health has improved significantly since 2004, has refused to cooperate and said last year he wanted to "close that chapter" in his life.
