Poroshenko doesn't appear for interrogations / Photo from UNIAN

According to Radio Free Europe / Radio Liberty, Poroshenko's lawyer, Ihor Holovan, said on Facebook that his client did not appear at the SBI headquarters in Kyiv on May 26 because the summons for questioning was "illegal" since his client should have been served the subpoena personally, which was not the case.

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Holovan called his client "the main political rival" of incumbent President Volodymyr Zelensky and claimed that the case in question, as well as other cases against Poroshenko, were politically motivated.

The SBI said earlier that it had summoned Poroshenko for questioning in a case about "the circumstances of moving across the Ukrainian border, without presenting to customs services, a collection of cultural objects, consisting of 43 paintings by world-famous artists."

Poroshenko, who is currently a deputy in parliament, has been questioned as a witness several times in recent months in cases looking into several investigations launched after he failed to win a second term as president.

The SBI said in January that it was looking into 13 possible cases where Poroshenko or his associates were implicated.