Russian President Vladimir Putin said he's on first-name terms with Donald Trump, as he praised the U.S. leader's record and blamed allegations of collusion between the Kremlin and the White House on "spy-mania."

"We see some quite serious achievements, even in this short period of time that he's been working," Putin said at his annual press conference in Moscow on Thursday. "Look at the markets, how they've risen. That shows investors' confidence in the American economy, it shows they believe in what President Trump is doing in this area."

Accusations in the U.S. of ties between Russia and Trump administration officials "are all invented by people who are in opposition to Trump in order to make his work look illegitimate," Putin said. Those involved show a lack of respect for Trump's voters, he said. He and Trump, who's repeatedly highlighted surging U.S. stock markets as evidence his political agenda is succeeding, use first names during their discussions, Putin said.