HANOI, Vietnam — President Trump suggested Saturday that he believes Vladimir Putin's claims that Russia did not interfere in last year's presidential election, trashing U.S. officials who have said Moscow meddled.

Trump singled out former CIA Director John Brennan, former National Intelligence Director James Clapper, and former FBI Director James Comey, all of whom have cited evidence about Russia election activity in 2016.

"They're political hacks," Trump told reporters aboard Air Force One. "I mean, you have Brennan, you have Clapper, and you have Comey. Comey is proven now to be a liar and he's proven to be a leaker."

Trump's decision to fire Comey in May is the subject of an obstruction of justice investigation by Special Counsel Robert Mueller’s office. It is also probing Russian election interference and any links to Trump campaign associates.

Hours later, early Sunday morning in Hanoi, Trump tweeted out a defense of his comments, saying it was important to have a good diplomatic relationship with Putin and Russia.

Meeting with reporters after brief meetings with Putin on the sidelines of an economic summit in Asia, Trump said the Russian leader agreed to renew efforts to defeat the Islamic State in Syria — and that Putin vehemently denies interfering in the U.S. election.

“He said he didn’t meddle,” Trump told reporters while en route to Hanoi for meetings with Vietnam leaders.

Trump said he asked Putin again about the allegations, “you can only ask him so many times. ... He did not do what they are saying he did.”

"Every time he sees me he says I didn’t do that and I really believe that when he tells me that, he means it," Trump said. "But he says I didn’t do that. I think he is very insulted by it, which is not a good thing for our country."

Mueller and congressional committees are investigating Russian efforts to influence the election on Trump’s behalf by posting fake news on social media websites and hacking email accounts of top Democrats.

When asked if he believes Putin’s denials, Trump said, “I think that he is very, very strong in the fact that he didn’t do it."

The president's statements drew a sharp reaction from Rep. Adam Schiff, of California, the top-ranking Democrat on the House Permanent Select Committee on Intelligence, which is investigating possible collusion between the Trump team and Russia.

"The President fools no one. He understands that the Russians intervened through the hacking and dumping of his opponent’s emails, the fruits of which he exploited time and again on the campaign trail," he said in a statement.

Schiff added: "He understands all this and more. He just doesn’t understand how to put country over self. Or to put it in terms he is more familiar with — Mr. Trump simply can’t bring himself to put America first."

Former deputy attorney general Sally Yates called Trump's statements "disturbing and shamelessly unpatriotic, on Veterans Day no less." Yates was fired as acting attorney general in January after refusing to defend Trump's temporary ban on travel from seven Muslim-majority countries.

Even some Republicans criticized Trump for taking Putin’s word over that of the U.S. officials.

“There's nothing ‘America First’ about taking the word of a KGB colonel over that of the American intelligence community,” said Sen. John McCain, R-Ariz.

Trump said he and Putin had “two or three short conversations” on the sidelines of the Asia-Pacific Economic Cooperation summit in Da Nẵng, Vietnam. He said they mostly discussed Syria, and agreed to a statement on the subject.

In a statement released hours before the White House said anything about the Putin chats, the Kremlin said “the presidents confirmed their determination to defeat ISIS (the Islamic State) in Syria.”

In seeking a political and diplomatic way forward, the Kremlin said Trump and Putin “agreed that there is no military solution to the conflict in Syria.”

Russia has been the major ally for Bashar Assad’s government in Syria. The United States has backed rebel groups and led a coalition carrying out airstrikes against ISIS positions in Syria.

McCain also took aim at the Putin-Trump statement on Syria: “There's no ‘principled realism’ in cooperating with Russia to prop up the murderous Assad regime, which remains the greatest obstacle to a political solution that would bring an end to the bloodshed in Syria.”

Trump and Putin did not have a formal bilateral meeting, as they did during the G-20 summit in Germany in July; these were informal talks in and around APEC meetings.

Private "pull-asides" at summit meetings have drawn criticisms of Barack Obama and previous presidents who have engaged in them. There is no formal record of what was said, and aides often give different interpretations of the brief conversations.

In his half-hour meeting with reporters aboard Air Force One, Trump said the Syria statement is “going to save tremendous numbers of lives, and we did it very quickly, we agreed very quickly.”

Trump said he also asked Putin to do something about unrest in Ukraine and to put pressure on North Korea to end its nuclear weapons program. “He could really help us on North Korea,” Trump said.

In an extended conversation with reporters, Trump touted the success of his week-long Asia trip that took him to Japan, South Korea and China before the APEC summit in Vietnam.

In a speech to APEC on Friday, Trump argued that too many countries are taking advantage of the United States when it comes to trade, and he will try to stop it.

As for his diplomatic efforts, the president claimed that Japan and South Korea “are now getting along much better,” and “that was great.”

Trump also said he made progress with Chinese President Xi Jinping on trade and North Korea.

"China likes me,” Trump said.

Trump completes his Asia trip early next week after more meetings with Asia-Pacific leaders at conferences in the Philippines.

Trump also said he will likely meet with Putin again in the future.

"We'll have a meeting," Trump said. "We have the potential to have a very good relationship."

Contributing: Nicole Gaudiano, USA TODAY

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