OSAKA, Japan – Three years after Russian efforts to influence the 2016 election triggered federal investigations, President Donald Trump asked Vladimir Putin on Friday not to do it again in 2020 – though he did so quickly and playfully.

"Don't meddle in the election, president," Trump said in a joking manner to Putin as cameras clicked and reporters shouted questions. Wagging a finger at the Russian president, Trump repeated, "don't meddle in the election."

When an interpreter translated Trump's "request," Putin laughed.

Later, a White House readout of the meeting said Trump and Putin discussed arms control, Iran, Syria, Venezuela and Ukraine – but said nothing about election interference.

Trump's light-hearted manner did not go down well with critics who accused him off laughing off a legitimate threat from an autocrat who has a grudge against the United States.

"Trump consistently appeases Putin at expense of US national security interests," tweeted Michael McFaul, an American ambassador to Russia during the Barack Obama administration.

It was yet another remarkable Trump-Putin moment, nearly a year after a landmark news conference in Helsinki in which Trump appeared to agree with Putin's denials that Russia interfered in the 2016 presidential election by hacking Democrats.

In Osaka, after a reporter asked Trump if he would tell Putin not to meddle in 2020, the president said, "Yes, of course, I will." He then turned to the Russian leader to make his joke.

The entreaty came after opening statements in which Trump said that "it's a great honor to be with President Putin," and that they would discuss issues like trade and nuclear disarmament. He said nothing at that point about election interference.

"We have a very very good relationship and we look forward to spending some very good time together," Trump said. "A lot of very positive things are going to come out of the relationship."

Putin, via a translator, said he was looking forward to the session with Trump.

"We haven't seen each other since Helsinki," he said.

Earlier in the day, Trump could be seen walking with Putin and gently patting him on the back just before the G-20 delegates posed for a group picture. Trump could also be seen amiably chatting up Saudi Crown Prince Mohammed bin Salman, who stood next to him for the photo.

This was the first face-to-face meeting between Trump and Putin since former special counsel Robert Mueller issued a report on Russian efforts to interfere in the 2016 presidential election in order to benefit Trump.