 His other close aides were Georgy Shakhnazarov and Anatoly Chernyaev.Gorbachev was aware that the Politburo could remove him from office, and that he could not pursue more radical reform without a majority of supporters in the Politburo.He sought to remove several older members from the Politburo, encouraging Grigory Romanov, Nikolai Tikhonov, and Viktor Grishin into retirement.