A column of people marched through the streets of Belgrade on Saturday evening in the fifth such protest against political violence in the country and putting more pressure on the government to fulfil their demands.
The president told RTS late on Thursday that he "knows neither who came up with it, nor when Thaci was told this," and also wondered, "what are we supposed to sign."
As he pointed out, a Kosovo solution is not in sight, and added that he had "stressed this before."
Vucic also said that Serbia is often "falling into the trap of the fake quarrels taking place in Pristina."
Protesters have sent their demands to Serbia's public broadcaster RTS.
According to the organizer's announcement, "Radio Television Serbia (RTS) should be a public service for all citizens, instead, it is an accomplice in concealing the truth and creating a parallel, false reality that Aleksandar Vucic has been creating for six years."