The head of state-owned oil giant Rosneft failed to appear as a witness in a high-profile embezzlement trial on Monday in order to attend a meeting between President Vladimir Putin and Turkish leader Recep Tayyip Erdogan.

Former Economic Development Minister Alexei Ulyukayev faces up to 15 years in prison on charges of soliciting a $2-million bribe from Rosneft’s CEO Igor Sechin.

Sechin was summoned to attend the high-profile trial as a witness on Monday but failed to appear in court in Moscow. Rosneft’s spokesman said that the CEO hadn’t received the summons.

The judge said Rosneft officials refused to accept the summons letter which was delivered by e-mail, fax, and in person, the Meduza news site reported.

Russia’s state-run postal service said it handed over the summons “at the place of delivery,” according to the RBC business portal.

A source close to the Russian delegation and Sechin's acquaintance told the Vedomosti business daily later that Sechin was due to accompany Putin for talks with Turkey’s leader on Monday.

Kremlin spokesman Dmitry Peskov confirmed that Sechin, dubbed “Russia’s second most powerful man” for close ties to Putin, was due in Russia’s southern city of Sochi for the meeting with President Recep Tayyip Erdogan.

The Zamoskvoretsky District Court judge ruled in Moscow to issue a second summons to Sechin to testify at the next hearing on Nov. 15, Mediazona reported.

The first serving Russian cabinet member to be arrested since the fall of the Soviet Union, Ulyukayev denies the charges that he solicited a $2-million bribe from Sechin.

He accuses Sechin of conspiring with a retired senior FSB official and then-head of security at Rosneft to frame him.

Prosecutors said Sechin collaborated with the FSB in a sting operation to nab Ulyukayev at Rosneft’s office with a bag full of marked bills last year.