President Putin said Russia can not permit any of its political parties to be financed from abroad, saying no self-respecting country would allow this.
Addressing the first Kremlin meeting of the Council for Promoting Civil Society Institutions and Human Rights, a body with presidential oversight, Mr. Putin said he had received reports that money allocated from abroad was being used to pay for, what he called, "sensitive political activities."
President Putin did not identify which foreign nations allegedly engage in this practice, nor did he specify how such activities were sensitive in nature or provide any other proof or details.
The Russian president's comments raised immediate alarm among civil society and human rights activists in Russia who say the move, if carried out, could spell the end of civil society and democratization programs in Russia.
Russian officials are widely perceived to be privately nervous about outside support sparking a people's uprising in Russia, much like those seen in Georgia, Ukraine, and Kyrgyzstan.
Russian, Ukrainian and Kyrgyz politicians have alleged that U.S. funding of NGOs was instrumental in helping opposition leaders topple long-time, Soviet-style leaders in their countries. It is a charge the United States and the new regimes in those former Soviet Republics deny.
President Putin's comments on foreign NGOs came just hours before he met with the visiting Belarus president, Alexander Lukashenko, the man often referred to in the West as Europe's last dictator.
Belarus is often mentioned as another possible place where popular protests could be sparked, due to the lack of tolerance for any political opposition or opposition media.
Before sitting down with his Belarussian counterpart, President Putin was warned by a Kremlin-connected foreign policy analyst that the human rights situation in Belarus is worsening.
The analyst, Sergei Karaganov, who heads the Council for Foreign and Defense Policies, said many Russians are among those falsely accused and jailed in Belarus for minor economic crimes. Mr. Karaganov also criticized moves against Russian media in Belarus and, what he called, the country's "prevailing culture of fear."
Mr. Karaganov said if the situation is allowed to continue unchecked, bloody events could be provoked by the local population or by those who he said compete with Russia from abroad.
President Putin said he would raise the issue during his two days of talks with Mr. Lukashenko, which continue Thursday.
The two leaders have said the main focus of their talks will be the proposed union between Russia and Belarus. The plan calls for closer political, economic, and military ties between the two predominantly Slavic nations, but stops short of creating a single state.