BERLIN — First came President Donald Trump’s scrapping of a proposed summit in Budapest, Hungary, on the war in Ukraine and his imposition of sanctions on Russia.

Then came the announcements by Russian President Vladimir Putin that Russia had successfully tested two menacing nuclear-capable weapons designed for possible doomsday combat against the United States.

The timing may not have been coincidental, analysts say, and Putin’s point was clear: Given the serious threat of Russia’s nuclear arsenal, the United States will ultimately need to respect Moscow’s power and negotiate — like it or not.

It’s a message the Kremlin has relied on in its brinkmanship with the United States dating to the days of the Cold War, when the Soviet Union regularly emphasized that for the world’s two biggest nuclear powers, negotiation was a necessity, not an option. More recently, Moscow has underscored that attempts to isolate Russia, including with the recent U.S. sanctions on Russian oil producers, were doomed to fail.

“What they are trying to say is you cannot just sanction us in any way you please, we are a major nuclear power and you need to engage in talks,” said András Rácz, a senior fellow at the German Council on Foreign Relations.

Trump returned to the White House early this year determined to broker an end to the war in Ukraine. In the days since, Moscow has tried unsuccessfully to turn those talks into a wider negotiation that would encompass business, energy and nuclear matters, looking to strike a “package deal” that could be more beneficial to the Kremlin.

“The only sector in which Russia is in near parity with the United States is of course weapons of mass destruction,” Rácz said. “So in order to have leverage, they have to include the nuclear question in the package deal. The Soviets did the same. The Soviet economy was incomparable to the scale of the U.S. economy in world trade. The real bargaining chip the Soviets had was their nuclear arsenal.”

So far, the effort by the Kremlin has failed, and Trump has signaled he won’t strike business or energy deals until Moscow ends the war. But nuclear weaponry is one area where Moscow may see an opening to draw in Washington.

In September, Putin proposed that Russia and the United States extend caps on long-range nuclear weapons for a year beginning in February. Trump responded by calling the offer a “good idea.”

This past week, Putin touted his new weapons first unveiled in 2018, which are designed to penetrate U.S. missile defenses. They would ensure that Russia can continue to threaten the United States with mutually assured destruction, regardless of Trump’s plans for an enhanced “Golden Dome” missile defense shield.

Last weekend, Putin described the results of a test Oct. 21 of the Burevestnik, a low-flying, nuclear-propelled Russian cruise missile capable of carrying nuclear warheads. Then, on Wednesday, the Russian leader said Moscow had tested the Poseidon, a long-range, nuclear-powered underwater drone.

The tests may have been planned well before the negative turn in relations between Putin and Trump.

“I don’t think that was linked to any kind of recent political developments,” said Pavel Podvig, an analyst based in Geneva who directs the Russian Nuclear Forces Project. He noted that Putin could have more directly threatened the United States in announcing the test results but did not.