It is reported that at the meeting, Putin demanded a clarification from Yanukovych about Trump’s former advisor, Paul Manafort.
The point is that Donald Trump had to dismiss Paul Manafort from his post of advisor due to a corruption scandal. The information that Manafort has received 13 million dollars directly from the treasury of the Ukrainian "Party of Regions" was released on the social media.
Thus, the Kremlin has lost its man at the headquarters of the US presidential candidate Trump because of his corrupt relations with the former Ukrainian government.
As reported, Yanukovych denied transferring money to the US official. However, Vladimir Putin did not believe him.
Donald Trump has already made several statements against the current policy of the Kremlin; in particular, he accused Russia of disrupting the ceasefire in Syria. This may indicate that Putin loses control over potentially "his" candidate.