Washington: US President Donald Trump admitted on Wednesday "something happened" with regards to Russian meddling in the 2016 election, suggesting he is supportive of investigations into the matter.

In a White House interview with Reuters, Trump said he directly asked Russian President Vladimir Putin if he was involved in what US intelligence says was Russian involvement in the campaign and that Putin had insisted he was not.

Trump said he spent the first 20 or 25 minutes of his long meeting with Putin at the G20 summit Hamburg on Friday, on the election meddling subject.

"I said, 'Did you do it?' And he said, 'No, I did not. Absolutely not'. I then asked him a second time in a totally different way. He said absolutely not," Trump said.