Trump is not incorrect, the dishonest press proved it many times already, like nonsense about Russian involvement in US elections.

German intelligence authorities found no concrete proof of disinformation campaigns targeting the government. 

As reported by Süddeutsche Zeitung, a long investigation by  BND (Germany's equivalent of the CIA) and its domestic counterpart, the Verfassungsschutz (BfV),  into potential Russian interference with German politics has failed to uncover evidence of Kremlin-backed meddling, Süddeutsche Zeitung reported Monday.  A conclusion that Germany's foreign and domestic intelligence agencies came to last fall, following investigation which was delivered to Merkel's chief-of-staff Peter Altmaier in the form of a 50-page report.  Altmaier chose not to make the report public, but it was leaked to the newspaper this week.