Rybkin has been out of touch since Thursday evening; his election HQ says it has no information on the candidate's whereabouts.
Election laws envisage access of a candidate's representative to airtime in exceptional cases.
The Central Election Commission will be guided by the right of a candidate and his headquarters to inform the voters of his or her program, Veshnyakov said.
However, the HQ of the missing candidate was negative about it. "I don't see anyone of us who could substitute for Ivan Rybkin. All the rest in our team are non-public politicians, and the debates will turn out a farce," HQ head Ksenia Ponomaryova said.