US President Donald Trump has said he holds Russian leader Vladimir Putin personally responsible for Russian interference in the 2016 US presidential election.

In an interview broadcast with CBS News, he said Mr Putin must be held responsible for what happens in Russia.

He said he had made clear to Mr Putin at their summit in Finland this week that Russian meddling had to stop.

Mr Trump's assertions about Russia since he returned to the US are in sharp contrast to his comments at a joint news conference in Helsinki with Mr Putin.