"I don't know him, but apparently he is an old hand. Don't know what he is doing to Russia, but I believe that at some point we'll know," said he.

The host asked the President to give short characteristics a number of well-known personalities.

With regard to Putin, trump has used the colloquial expression "tough cookie", which also can be translated as "snatch", "die hard" and "man does not miss".

During the election campaign, trump promised a "very good relationship" with Putin, but amid criticism in Congress and the media, accusations of some of his entourage in behind-the-scene contacts with Russian officials, and especially suspicions that Russian hackers allegedly contributed to the discredit of his rival Hillary Clinton, he prefers to speak more diplomatically.