Despite Polish requests, Prussia refused to honour its alliance obligations. In the end, the numerical superiority of the Russians was too great, and defeat looked inevitable. Poniatowski's attempts at negotiations with Russia proved futile. In July 1792, when Warsaw was threatened with siege by the Russians, the king came to believe that surrender was the only alternative to total defeat. Having received assurances from Russian ambassador Yakov Bulgakov that no territorial changes would occur, a cabinet of ministers called the Guard of Laws (or Guardians of Law, ) voted eight to four in favor of surrender. On 24 July 1792, Poniatowski joined the Targowica Confederation. The Polish Army disintegrated. Many reform leaders, believing their cause lost, went into self-exile, although they hoped that Poniatowski would be able to negotiate an acceptable compromise with the Russians, as he had done in the past. Poniatowski had not saved the Commonwealth, however. He and the reformers had lost much of their influence, both within the country and with Catherine. Neither were the Targowica Confederates victorious. To their surprise, there ensued the Second Partition of Poland. With the new deputies bribed or intimidated by the Russian troops, the Grodno Sejm took place. On 23 November 1793, it annulled all acts of the Great Sejm, including the Constitution. Faced with his powerlessness, Poniatowski once again considered abdication; in the meantime he tried to salvage whatever reforms he could.