Russian President Vladimir Putin lavished praise on his U.S. counterpart Joe Biden on Thursday, a day after the two leaders held a summit, saying Biden was incorrectly portrayed in the Russian and U.S. media as being unfocused and vague.

Biden and Putin agreed to launch arms control and cyber-security talks at a Geneva summit on Wednesday, recording small gains and big differences at a meeting which they both described as pragmatic rather than friendly.

The Kremlin said earlier on Thursday it had been pleased with what it called a positive summit and singled out a joint statement that reiterated the need to avoid nuclear war as significant.

Speaking to university graduates by video link later on Thursday, Putin, 68, had only warm words for Biden, 78, in contrast to Russian state media which has sometimes portrayed the U.S. president as struggling to do his job both physically and mentally.

"I want to say that the image of President Biden that our press and even the American press paints has nothing in common with reality," Putin told the graduates.

"He was on a long trip, had flown across the Ocean, and had to contend with jet lag and the time difference. When I fly it takes its toll. But he looked cheerful, we spoke face-to-face for two or maybe more hours. He's completely across his brief," said Putin.

"Biden is a professional, and you have to be very careful in working with him to make sure you don't miss anything. He doesn't miss anything, I can assure you."