President Donald Trump’s performance at a joint news conference with Russian President Vladimir Putin on Monday has drawn criticism from many quarters for his siding with Moscow against the U.S. intelligence community.

According to multiple experts, the U.S. leader’s focus appeared to be not on his country’s interests — but rather on his own.

“Trump is clearly playing to his domestic base, they love it. If you look at poll numbers now among his base, their view of Russia and Putin is going up,” said Angela Stent, Georgetown University professor and director of the university’s Center for Eurasian, Russian and East European Studies.

“Never in the history of U.S.-Soviet or U.S.-Russian relations has an American president essentially said that he doesn’t agree with his own intelligence agencies, criticized them and essentially agreed with a Russian president who is a former KGB case officer,” she added. “No one has ever seen something like this before. It is unprecedented and it really does raise questions about what really is going on, why he would possibly say that in a public press conference.”

University of Hong Kong Associate Professor in European Studies Stefan Auer echoed that sentiment, telling CNBC that Trump “regrettably is more and more preoccupied with himself rather than the interest of the U.S., the West, or whatever is left of the global order.”

At the news conference during the long-awaited Trump-Putin summit, the American president said he has “great confidence” in the U.S. intelligence community, but claimed that Putin was “extremely strong and powerful in his denial” that Russia meddled in the 2016 U.S. presidential election.

The briefing took place three days after Justice Department Special Counsel Robert Mueller indicted 12 Russian nationals for interfering in the U.S. election.

“It was not a good summit. It was an embarrassing performance by President Trump. Not only did he take at face value President Putin’s denial of election interference, he took that over the judgement of his own intelligence community,” said Steven Pifer, a non-resident senior fellow at think tank Brookings Institution who served as the U.S. ambassador to Ukraine under Democratic President Bill Clinton.

Pifer said the summit was a missed opportunity for Trump to push Putin on some Russian interference in U.S. elections, aggression in Ukraine and the fighting in Syria. Such discussions, he said, could potentially bring about change in the Kremlin’s policies and form a better basis for U.S.- Russia relations.

“I worry that Mr. Putin goes back to Moscow thinking, ‘I got no criticism. I can continue these policies.’ And in some cases these policies are very detrimental to American interests,” Pifer told CNBC.

As for Russia, its leadership appeared to celebrate how the summit turned out.

Following the meeting, Russian Foreign Minister Sergey Lavrov reportedly said the summit went “better than super.” Pifer compared the statement with the criticism from politicians in the U.S.: “I don’t see anyone on the American side offering similar comments.”

— CNBC’s Amanda Macias and Tucker Higgins contributed to this report