MOSCOW — A liberal-leaning policy organization that advises President Dmitri A. Medvedev on Wednesday recommended a startling agenda of long-term changes, including restoration of elections for governors, an end to censorship of the news media, Russian membership in NATO and dissolution of the Federal Security Service, successor to the Soviet-era K.G.B.

Igor Y. Yurgens, director of the Institute of Contemporary Development, said at a news conference that unless Russia modernized, it risked losing its brightest young people to the West and aggravating internal tensions to the point where Russia itself could break up. He said the institute’s new report, “Twenty-first Century Russia: An Image of the Desired Future,” was written to avoid this chain of events.

“We have a very simple choice in Russia,” said Yevgeny Gontmakher, one of the report’s authors. “Either we can gradually but decisively evolve along the lines that we are suggesting, or we will head into one of the regular revolts that we have had more than once in the last 20 years.”

Mr. Yurgens’s institute has regularly called for liberal reforms, and it is not considered to have particular sway over Mr. Medvedev, who serves as chairman of its board of trustees. But Wednesday’s report contained the group’s boldest proposals to date, and drew immediate rebukes from conservative lawmakers who said liberals were trying to take Russia back to the chaotic 1990s and the age of Boris N. Yeltsin.

“The institute’s mistake is that it idealizes that time,” said Sergei A. Markov, a deputy with United Russia, in remarks on the party’s Web site. “That period created all the preconditions for dictatorship. And only the policies of Vladimir Putin, by some miracle, allowed us to escape it.”

The presentation came during a week of political debate that was, by Russian standards, unusually raw. Sergei M. Mironov, the speaker of Russia’s upper house of Parliament, set off a barrage of criticism on Monday night when he told a television interviewer that the leaders of his party “categorically oppose the budget proposed by Vladimir Putin,” now the prime minister, who still dominates Russian politics. Mr. Mironov is the head of Just Russia, an opposition party that nonetheless has close ties to the Kremlin.

Mr. Mironov took care to add that he supported “everything in Putin’s foreign policy and certain decisions in home policy,” but members of United Russia, which Mr. Putin heads, reacted furiously. In a statement on the party’s Web site, one official, Andrei Isayev, called for Mr. Mironov to resign, and said Mr. Mironov “thinks that the situation has become shaky because of the crisis and he is trying to run from the ship like a rat.”

Alexei V. Markarkin, an analyst at the Center for Political Technologies, said there were signs of a loosening in Russian public discourse, in which “those questions which were too dangerous to discuss can now be discussed.” He pointed to the large protest held over the weekend in Kaliningrad, where complaints about tax increases and high utility costs were sprinkled with calls for Mr. Putin’s ouster.

“There is a protest spirit related to the crisis,” he said. “Kaliningrad is not a rule, but it is a signal.”