RUSSIAN President Boris Yeltsin, putting his power and prestige on the line, said yesterday he wanted to take charge of the government and introduce wide-ranging radical reforms, including the lifting of price controls.Speaking at the opening of the Russian Congress of People's Deputies, the republic's lawmaking body, Mr. Yeltsin defended the freeing of prices, saying all talk about introducing a market economy in the republic would be "empty chatter" unless such a measure was taken. "It is time to act decisively, harshly, without hesitation," Yeltsin said in a determined tone. "We won't be able to carry out reforms painlessly. The first step will be the most difficult." Since the decisive defeat of hard-liners during the failed August coup, the reformist forces headed by Yeltsin have accomplished little in transforming the country into a democratic, market-based state. The Russian government, beset by political infighting, has proved ineffective at coping with the rapid economic decline of the nation. As a result, public opinion has been turning against the Russian president. Yeltsin is seeking to jolt the deadlocked government into action by taking over the reins himself. Yeltsin offered to become prime minister in addition to his post as president, but stressed the changes would be made on a one-year basis only. Russia has been without a prime minister since Ivan Silayev left the post to head the Inter-republican Economic Committee several weeks ago. "The congress should give the president the right to change, either on his own or with the subsequent endorsement by the Supreme Soviet [parliament], the existing structures of top executive bodies and decide problems linked with their composition," said Yeltsin. During his speech, Yeltsin said 55 percent of families were living below the poverty line. He added that in order to stabilize the Russian economy, strict measures would be taken to control the money supply and the government budget deficit. He also announced his intention to reform the tax structure "to stimulate the production of goods" and speed up privatization of property. "If we don't start controlling the printing of the ruble ... the result could be hyperinflation," Yeltsin said. Russia wants to work with other republics on solving the economic crisis and controlling the money supply, the president said. But if the recently signed economic treaty proves ineffective, Russia is prepared to take measures on its own, including the printing of its own money, Yeltsin said. In addition, Yeltsin said that although Russia wanted to form a national guard, it would seek to preserve a united military comprising the 12 former Soviet republics. At least one republic, the Ukraine, has announced it will create its own army. If the Ukraine proceeds as planned, Russia will have no other option than to form its own army, Yeltsin indicated. Yeltsin didn't say specifically when radical reforms would begin, but predicted if all went according to plan the economy would begin to stabilize by the fall of 1992. Russian deputies reacted favorably to Yeltsin's speech. Andrei Kokoshin, deputy director of the USA-Canada Institute, compared the reform blueprint to the "shock therapy" plan carried out in Poland, adding it was a "courageous decision" on Yeltsin's part. "In some cases it will be more painful here because the Poles were better prepared," he said. Liberal legislator Viktor Sheinis supported Yeltsin but said the possible government changes made him nervous. "I have my doubts about combining the positions of president and prime minister," he said. "I also would have liked to hear something more concrete on how he intends to accomplish his goals."