KYIV, Ukraine — In an impassioned speech upon receiving the Nobel Peace Prize on Saturday, the laureate from Ukraine seized the moment to make an incongruous but powerful point: At this moment in history, she said, the only way to secure democracy, human rights and a lasting peace in Ukraine is to fight.

“People of Ukraine want peace more than anyone else in the world,” said Oleksandra Matviychuk, who accepted the prize on behalf of the Center for Civil Liberties in Ukraine, which she heads. “But peace cannot be reached by a country under attack laying down its arms. This would not be peace, but occupation.”

The other two laureates — Memorial, a Russian research and human rights organization, and Ales Bialiatski, a jailed Belarusian activist — have also become symbols of resistance and accountability during the largest ground war in Europe since World War II, set off by Russia’s invasion of Ukraine.

Memorial is known for its efforts to uncover the crimes of the Soviet era, but Jan Rachinsky, its chairman, who accepted the award for Memorial, said that his organization does more than research and document the tragedies of the past, extending its efforts to the “acute social conflicts of the present.”

“What we see as the root cause of these crimes is the sanctification of the Russian state as the supreme value,” he said in his speech. “This requires that the absolute priority of power is to serve the ‘interests of the state,’ over the interests of individual human beings, and their freedom, dignity and rights.”

This “inverted system of values,” he said, “prevailed in the Soviet Union for 70 years and, regrettably, continues until today.”

“One of the obvious effects of the sanctification of the state was the rise of imperial ambitions,” he said. It also allows for “impunity, not only for those who make criminal political decisions, but also for those who commit crimes in the execution of those decisions.”

“We saw this in the hostilities in Chechnya, and we see it happening again today in the occupied territory of Ukraine,” he said. “Regrettably, Russian society did not have the strength to break the tradition of state violence.”

In her acceptance speech, Ms. Matviychuk of the Center for Civil Liberties in Ukraine said the international system designed after World War II has been severely undermined, and called on world leaders to “stop pretending deferred military threats are ‘political compromises.’”

“The democratic world has grown accustomed to making concessions to dictatorships,” she said. “And that is why the willingness of the Ukrainian people to resist Russian imperialism is so important.”

A desire for peace does not mean peace at any cost, she said, and her country cannot “leave people in the occupied territories to be killed and tortured.”

“People’s lives cannot be a ‘political compromise,’” she said. “Fighting for peace does not mean yielding to pressure of the aggressor, it means protecting people from its cruelty.”

Before the ceremonies, which were held in Oslo, Russia launched more than a dozen Iranian-made attack drones in a predawn assault on targets in Ukraine’s south, knocking out power in the city of Odesa and the surrounding region.

In his nightly address, President Volodymyr Zelensky of Ukraine said that the situation was “very difficult” in parts of the Donbas region in eastern Ukraine, with the fighting around Bakhmut particularly vicious. He said overnight that Russian forces had “destroyed” Bakhmut, turning the city, once home to 70,000 people, into “burnt ruins.”

The Nobel committee’s decision to group a Ukrainian civil society organization with human rights defenders from Russia and Belarus prompted some initial backlash in Ukraine when the award was announced in October. Some saw it as an affront to those who have been working to protect Ukrainians since Russia invaded the country in February.

Mykhailo Podolyak, a senior adviser to Mr. Zelensky, issued a scathing criticism of the Nobel committee, saying that it had an “interesting understanding of the word ‘peace.’”

“Neither Russian nor Belarusian organizations were able to oppose this war,” he said in a statement.

Berit Reiss-Andersen, the chairwoman of the Norwegian Nobel Committee, said before the ceremony that the awards were given to send a signal that the conflict in Ukraine must end.

“Sometimes an effort for peace lies with civil society and not with state ambitions alone,” she said. “Peace is a wish and achievement that comes with a value that all laureates work for: addressing atrocities, war crimes and rule of law.”

She said that a disregard for those values was at the core of Russia’s war in Ukraine.

“Exactly in these times this is a very important reminder,” she said.

Natalia Pinchuk, the wife of Ales Bialiatski, received the prize on her husband’s behalf. He was detained in Belarus following protests in 2020 against the re-election of the Belarusian president, Alexander Lukashenko, and remains in jail without trial. He faces up to 12 years in prison if convicted.

Mr. Lukashenko allowed his country to be used as a staging ground for Russia’s invasion of Ukraine, and Russian bombers continue to use Belarusian air space to launch missile strikes across Ukraine. The massing of Russian soldiers there recently has led to repeated speculation that Belarus may be preparing to intervene in the conflict on the Kremlin’s behalf.

Ms. Pinchuk said that today’s political and military events “threaten Belarus with the loss of statehood and independence.”

“Unfortunately, the authorities choose to engage with society through the use of force — grenades, batons, stun guns, endless arrests and torture,” she said. “There is no effort or talk about national compromise or dialogue.”

It was precisely that kind of violent oppression that Ms. Matviychuk said Ukraine was fighting to prevent, framing the war as part of a broader struggle between competing visions of the world.

“This is not a war between two states, it is a war of two systems — authoritarianism and democracy,” she said. “We are fighting for the opportunity to build a state in which everyone’s rights are protected, authorities are accountable, courts are independent and the police do not beat peaceful student demonstrations in the central square of the capital.”

Ms. Matviychuk concluded her address with a plea for support and solidarity in that fight.

“You don’t have to be Ukrainians to support Ukraine,” she said. “It is enough just to be humans.”