Stanley Kubrick should have lived to see this day. Only the director of the nuclear war satire “Dr. Strangelove” could do full justice to the fact that, long after the demise of the Soviet Union, a Russian leader would return to the bombast and bluster of the Cold War.

Two announcements from the Kremlin yesterday confirmed that President Putin is slowly turning back the clock. Incensed that America and its European partners are building a missile defense system in Eastern Europe, the Russian military said it had successfully tested a non-nuclear “thermobaric” weapon comparable in its destructive effects to a nuclear bomb.

“The tests have shown that the new air delivered ordnance is comparable to a nuclear weapon in its efficiency and capability,” a deputy chief of Russia’s General Staff, Colonel General Alexander Rukshin, said.

Tightening his grip on the Kremlin, Mr. Putin yesterday sacked his prime minister, Mikhail Fradkov, and Cabinet, nominating a loyal ally and member of his inner circle, Viktor Zubkov, as the new premier. The choice came as a surprise to Kremlin watchers both inside and outside Russia.

The little-known Mr. Zubkov, 65, formerly in charge of tax collection, was until yesterday in charge of investigations into money laundering, the means by which Mr. Putin has kept close control over the rich businessmen who run Russian industry as personal fiefdoms while showing scant concern for the law.

Mr. Zubkov worked closely for a number of years with Mr. Putin in the mayor’s office in St. Petersburg. His daughter is married to Anatoly Serdyukov, whom Mr. Putin this year appointed as defense minister.

Because of term limits, Mr. Putin cannot stand for a third four-year presidential term in the election in six months’ time, which suggests the promotion of Mr. Zubkov is a way for Mr. Putin to maintain his influence over the new president.

A leading member of the opposition Yabloko party, Sergei Ivanenko, told the Associated Press that the surprise appointment was similar to Mr. Putin’s own selection as prime minister by President Yeltsin in August 1999. Four months later, Putin became the acting president, then won the presidential election in March 2000.

The leader of Yabloko, Grigory Yavlinsky, said yesterday that he believes Mr. Putin is maneuvering to hold on to power once his presidency ends. “The appointment of a person without political face as prime minister of a great nation in this difficult time means that the president is the only source of power,” he told the AP. “The appointment is a move toward the effective extension of Vladimir Putin’s rule even after his authority formally ends.”

Described as “the father of all bombs,” the new “fuel-air bomb” successfully tested yesterday provides a blast equivalent to 44 tons of TNT and, like the American “bunkerbuster” but four times more powerful, wreaks its destruction by the enormous shock wave that arrives in its wake.

The news of the new Russian superbomb comes on the heels of the resumption this summer of flights by a fleet of 14 Russian strategic bombers that had stood down after President George H.W. Bush and the last Soviet leader, Mikhail Gorbachev, agreed to abandon Cold War defenses.

Russian Tu-95 and Tu-160 nuclear bombers began to fly missions in August. The flights come close to the Alaska coast and to British airspace, prompting the scrambling of Royal Air Force and Norwegian NATO jets. Despite nuclear disarmament agreements, Russia continues to aim thousands of ICBM warheads at American targets.

This year, notwithstanding an apparently friendly visit to the Bush family retreat in Kennebunkport, Maine, Mr. Putin denounced American military power, abandoned a conventional arms agreement with NATO, and dispatched a submarine to make a claim for Russia territory under the Arctic ice cap.

Bolstered by the sharp rise in the price of oil, which has benefited the Russian economy, Mr. Putin has set himself the task of restoring Russia as a major power. He has not hesitated to threaten cutting off natural gas supplies to influence political events in the Eastern European countries of the old Soviet empire.

At home he has stifled dissent, silenced television stations by putting them under state control, and turned a blind eye to the assassination of Russia’s enemies. He has played down the importance of the murder of reporter Anna Politkovskaya, who criticized him for the brutality of his campaign against the Chechens, and declined to extradite the accused killer in London last year of the Russian dissident Alexander Litvinenko.

Yesterday, Russian authorities declared that the death of a defense journalist who reported on failed missile tests and secret weapons deals with Syria and Iran was suicide. Ivan Safronov died after falling from a window in his apartment building. “It turns out that an absolutely sober person for some reason decided to kill himself,” a Moscow deputy prosecutor, Vyacheslav Sapkov, said.