President Donald Trump says he is "very concerned" that Russia will try to meddle in November's mid-term elections to help the Democrats win.

President Trump wrote in a tweet he is "very concerned that Russia will be fighting very hard to have an impact on the upcoming election.

"They will be pushing very hard for the Democrats. They definitely don't want Trump!"

He does not explain his reasoning.

The US intelligence community concluded Russia meddled in the 2016 election to try to help Mr Trump win, and Russian President Vladimir Putin said last week at his joint press conference with the US president that he was rooting for the Republican.

The tweet is the latest example of President Trump sowing doubts about the integrity of the US electoral system.

In 2016, he repeatedly claimed the election was "rigged."