"Don't meddle in the election, please," Donald Trump has told Russia's Vladimir Putin, smiling and pointing a finger at those gathered to witness the meeting of the two leaders.

They have come face to face at the G20 conference in Japan, meeting for the first time since the US special counsel concluded that Russia extensively interfered with the 2016 campaign which saw Trump emerge as US president.

The tone of his comment, which evoked a laugh from the Russian president, will do little to quash speculation about the relationship between the two leaders.

It comes in the aftermath of an investigation in which special counsel Robert Mueller concluded that he could not establish a criminal conspiracy between Trump's campaign and Russia.

The pair met in Osaka, Japan, on Friday where they shook hands and gave a brief summary of issues they planned to discuss, including trade and disarmament.

The leaders shook hands and spoke about the issues they planned to discuss. Credit: AP

After a few opening remarks, a reporter then shouted to ask Trump whether he would be asking Putin "not to meddle" in the 2020 election.

The president answered "Of course," before turning to Putin and saying: "Don't meddle in the election, please."

He then smiled and repeated the request while pointing to those on Putin's side of the room.

The Russian president laughed in response.

During the press call, Trump also said he enjoyed a "very, very good relationship" with Putin, and said "many positive things are going to come out of the relationship."

They are among the leaders of the 19 most powerful countries in the world, the European Union and seven other guest countries gathered in Osaka, Japan, to discuss a range of international issues.

Between them, they represent more than 80% of global GDP and will be talking about global economy, trade and investment, innovation, environment and energy, employment, women’s empowerment, development and health.

Theresa May will also be meeting with President Putin, andtold ITV News she plans to urge him to hand over the two suspects in the Novichok poisoning case so they can face British justice.