 Complete the following phrase:  He was appointed Acting Prime Minister under President Boris Yeltsin in 1992 from 15 June until 14 December, when the anti-Yeltsin Russian Congress of Peoples Deputies refused to confirm Gaidar in this position and Viktor Chernomyrdin was eventually chosen as a compromise figure. Gaidar continued to advise the new government. On 18 September 1993, he was again appointed the First Vice-Premier under Chernomyrdin as a deliberate snub to the opposition. He played an active role in the 