BRUSSELS — President Joe Biden used his first appearance at a NATO summit since taking office to call on Russian President Vladimir Putin to step back from provocative actions targeting the U.S. and its allies on Monday. NATO leaders joined the United States in formally accusing Moscow and Beijing of malign actions.

Biden’s sharp words for Russia and his friendly interactions with NATO allies marked a sharp shift in tone from the past four years and highlighted the renewed U.S. commitment to the 30-country alliance that was frequently maligned by predecessor Donald Trump.

Biden, wearing a NATO lapel pin, said that in his extensive talks with NATO leaders about his planned meeting with Putin on Wednesday, all were supportive of his plans to press the Russian leader to halt Russian-originated cyber attacks against the West, end the violent stifling of political dissidents and stop interfering in elections outside its borders.

“I’m going to make clear to President Putin that there are areas where we can cooperate, if he chooses,” Biden told reporters as he ended his day at NATO headquarters. “And if he chooses not to cooperate and acts in a way that he has in the past relative to cybersecurity and other activities, then we will respond, we will respond in kind.”

Biden is on an eight-day visit to Europe in which he is seeking to rally allies to speak with a single voice on countering Russia and China.

NATO leaders on Monday declared China a constant security challenge and said the Chinese are working to undermine global order, a message in sync with Biden’s pleas to confront Beijing on China’s trade, military and human rights practices.

In a summit statement, the leaders said that China’s goals and “assertive behavior present systemic challenges to the rules-based international order and to areas relevant to alliance security.”

The heads of state and government expressed concern about what they said were China’s “coercive policies,” the opaque ways it is modernizing its armed forces and its use of disinformation.

The NATO leaders also took a big swipe at Russia in their communique, deploring what they consider its aggressive military activities and its snap war games near the borders of NATO countries as well as repeated violations of their airspace by Russian planes.

They said Russia had ramped up “hybrid” actions against member countries by attempts to interfere in elections, by political and economic intimidation, by disinformation campaigns and “malicious cyber activities.”

“Until Russia demonstrates compliance with international law and its international obligations and responsibilities, there can be no return to ‘business as usual,’ ” they said.

The North Atlantic Treaty Organization is an alliance of European and North American countries formed after World War II as a bulwark against Russian aggression. The new Brussels communique states plainly that the NATO nations “will engage China with a view to defending the security interests of the alliance.”

Biden arrived at the NATO summit after three days of consulting with Group of Seven allies in England, where he successfully pushed for a G-7 communique that called out forced labor practices and other human rights violations impacting Uyghur Muslims and other ethnic minorities in China’s western Xinjiang province.

However, differences remain among the allies about how forcefully to criticize Beijing.

German Chancellor Angela Merkel said NATO’s decision to name China as a threat “shouldn’t be overstated” because Beijing, like Russia, is also a partner in some areas. China is Germany’s top trading partner, and she said it is important to “find the right balance.”

France’s President Emmanuel Macron urged the alliance not to let China distract it from what he saw as more pressing issues facing NATO, including the fight against terrorism and security issues related to Russia.

“I think it is very important not to scatter our efforts and not to have biases in our relation to China,” Macron said.

The Chinese Embassy to the United Kingdom on Monday issued a statement saying the G-7 communique “deliberately slandered China and arbitrarily interfered in China’s internal affairs.”

Biden arrived at his first NATO summit as president as leading members declared it a pivotal moment for an alliance beleaguered during the presidency of Trump, who questioned the relevance of the multilateral organization.

Biden sat down with NATO Secretary General Jens Stoltenberg and underscored the U.S. commitment to Article 5 of the alliance charter, which spells out that an attack on any member is an attack on all and is to be met with a collective response.

“Article 5 we take as a sacred obligation,” Biden said. “I want NATO to know America is there.”

It was a contrast to the days when Trump called the alliance “obsolete.”