President Dmitry Medvedev Thursday sternly warned that the government won't allow “provocateurs and extremists” to undermine stability. Responding to the wave of protests over fraud-tainted elections, Medvedev proposed a set of reforms to liberalize Russia's political system. “Russia needs democracy, not chaos,” Medvedev said in his state-of-the nation address adding the government would strongly resist any foreign pressure. The statement follows massive rallies against fraud in the Dec. 4 vote, in which the main Kremlin party, United Russia, lost a quarter of its seats. Opposition leaders and independent election monitors said United Russia only managed to retain its majority by fraud. A rally in Moscow drew tens of thousands demanding a repeat vote and punishment for the officials involved in fraud, the largest show of discontent since the 1991 Soviet collapse. Another massive rally is set for this weekend. The protests dented the power of Prime Minister Vladimir Putin and signaled that his bid to reclaim the presidency in next March's election may not be as trouble-free as had been thought. Both Putin and Medvedev, who has been his loyal placeholder, firmly rejected the calls for a rerun, saying the vote reflected the people's will. Meanwhile, Medvedev appointed Deputy Prime Minister Sergei Ivanov as Kremlin chief of staff on Thursday, giving Vladimir Putin's close ally one of the most powerful jobs in Russia ahead of his expected return to the presidency next year. Ivanov, a former KGB spy who is seen as one of Putin's closest friends, is currently responsible for domestic military and technology policy.