Russian President Vladimir Putin praised US president-elect Donald Trump on Friday, saying Trump had his finger on the pulse of US society, and he launched a scathing attack on the Democrats, saying they had forgotten the meaning of their own name and were sore losers.

Speaking at his annual news conference in Moscow, Putin said that only Russia had believed that Trump would become the next president of the United States, but that did not mean the Democrats had the right to blame him for their defeat.

"The current administration and the leadership of the Democratic Party are trying to blame all their failures on external factors," Putin told reporters.

"(We are talking about) a party that has clearly forgotten the original meaning of its own name," Putin said, accusing the Democrats of "shamelessly" abusing their status as the ruling party to try to influence public opinion.

"Outstanding figures in US history from the ranks of the Democratic Party would likely be turning in their graves. Roosevelt certainly would be," he said.

The White House and US intelligence officials have accused Russia of trying to interfere with the US election by hacking Democratic National Committee accounts. Information from those hacks was leaked online, causing political problems for Democratic candidate Hillary Clinton.

Putin dismissed suggestions that Moscow had in any way helped Trump to win.

"It's not like that," he said. "All of this (the accusations) speaks of the current administration's systemic problems."

The question of who hacked the Democratic National Committee was not important, but what the hacks revealed - that public opinion in the United States was being manipulated - was, said Putin.

"They (the Democrats) are losing on all fronts and looking elsewhere for things to blame."