Oleh Rybachuk, Yushchenko's chief of staff, was among those who responded to the speculation. He said that neither he nor Yushchenko knows or has ever known Berezovskii, who was granted political asylum in the United Kingdom after an ill-fated foray into politics in Russia.
Other officials denounced the allegations about the Yushchenko campaign as a political ambush.
Acting Justice Minister Roman Zvarych said today that the allegations, even if true, would not constitute cause for impeachment.
"The word 'impeachment' is not a political term, and the president cannot be impeached for any political action," Zvarych said. "Only a crime can be a reason for starting impeachment procedures. If you talk about corpus delicti [body of crime], which gives a reason for impeachment, please refer to a specific article of the penal code."
Ukraine's first post-independence president, Leonid Kravchuk, is now a member of parliament and raised the charges yesterday. He said he has information that Berezovskii had provided at least $15 million to Yushchenko's campaign. If true, Kravchuk suggested, Yushchenko could be impeached.
Ukraine's Channel 5 quoted Berezovskii as saying that he had spoken with Kravchuk but that he had not told Kravchuk that he provided money for Yushchenko's campaign.
Ukraine has been embroiled in a major political crisis since Yushchenko dismissed the government
of Yuliya Tymoshenko amid a flurry of suggestions that corruption was rampant
and extended to the highest levels of government.
Berezovskii is wanted in Russia on fraud charges.
"Yushchenko Choice Represents 'Stopgap' Measure"