In Belgrade, Serbian Prime Minister Vojislav Koštunica refused to receive Ahtisaari. Koštunica claimed that because Serbia had still not formed a new government after the 21 January parliamentary elections he had no mandate to discuss Kosovo and therefore could not meet Ahtisaari. Nevertheless, he later denounced the proposal as "illegitimate and unacceptable" because he alleged it "violates the U.N. Charter ... by undermining the sovereignty of U.N. member Serbia." President Boris Tadić did receive Ahtisaari, after which he reaffirmed his vow to never accept an independent Kosovo. Foreign Minister Vuk Drašković warned that it was "necessary to avoid an imposed solution that could cause Serbia to become a factor of instability."