It is not known if Rosneft chief Igor Sechin will appear in a Moscow court to testify in a high-profile extortion trial on November 15.
Sechin -- a longtime former deputy chief of staff to President Vladimir Putin who is seen as a close ally -- has been summoned to Zamoskvoretsky district court for a second time in the trial of former Economy Minister Aleksei Ulyukayev.
Sechin failed to appear to give testimony in the trial on November 13.
Rosneft spokesman Mikhail Leontyev refused on November 14 to confirm whether Sechin, 57, would answer the second summons and appear in court.
"Rosneft's job is to engage in production. The press service has no obligation to give information about the company head's schedule," Leontyev told Interfax when asked whether Sechin would appear in court on November 15.
After Sechin failed to appear at the court on November 13, Judge Larisa Semyonova said Rosneft officials at the oil giant's Moscow headquarters had refused to accept the summons that was delivered by court officials.
Ulyukayev, who is being held under house arrest, is one of the highest-ranking officials to be arrested in Russia since the Soviet era.
He is accused of extorting a $2 million bribe from Sechin in exchange for his ministry's approval for Rosneft to acquire a majority stake in the regional oil company Bashneft.
Prosecutors say Ulyukayev, 61, was caught taking a case full of money from Sechin at Rosneft headquarters in a sting operation.
Ukyukayev's trial began in August. He says he is not guilty and accuses Sechin and the Federal Security Service (FSB) of tricking him by telling him the case was full of wine.
Putin fired Ulyukayev shortly after he was detained in November 2016.