Russian President Vladimir Putin has described leading Republican presidential candidate Donald Trump as "undoubtedly a very colourful, talented person".
The Republican has repeatedly praised Mr Putin's macho style and policies towards Syria, on the campaign trail.
The Russian president brushed off concerns about Mr Trump's controversial proposal to ban Muslims from the US.
He said Russia was ready to work with whoever was elected the next president.
"It is not our business to determine his merits, that is up to US voters," Mr Putin told reporters after his annual televised news conference. "But he is the absolute leader in the presidential race."
"He is a very outstanding person, talented, without any doubt."
New York billionaire Mr Trump has spoken warmly about Mr Putin's tough approach to foreign policy in the past.
I think that I would probably get along with him very well
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On Wednesday, he contrasted himself with President Barack Obama when he said: "I will get along - I think - with Putin, and I will get along with others, and we will have a much more stable - stable world."
Mr Trump has also backed Russian intervention in Syria, because Mr Putin said his target was Islamic State.
Relations between Mr Obama and Mr Putin have chilled in recent years following disputes over Ukraine and Syria.
Analysis: Anthony Zurcher, North America reporter, BBC News
Donald Trump likes to issue boastful press releases whenever he receives a new endorsement, but it will be interesting to see how he handles kind words from Vladimir Putin.
The Russian president has been a regular target of rhetorical heat from Republican candidates. New Jersey Governor Chris Christie said in the presidential debate earlier this week that he would impose a no-fly zone over Syria and shoot down any Russian planes that violated it. Former corporate chief Carly Fiorina has maintained that she would refuse to talk with the Russian leader, relying on US military force to speak for itself.
It is definitely too early to mark Mr Putin's comments as a negative for the New York businessman, however. The Russian leader has long been admired by conservatives who say his resolute demeanour and toughness are qualities lacking in the current White House occupant. Talk to Trump supporters, and they'll tell you those are exactly the kind of attributes they admire in their man.
If Mr Putin views Mr Trump as a political soul-mate, that's likely just fine with them.
The Russian president appeared to welcome Mr Trump's overtures.
"He wants to move to another level of relations, a closer, deeper level of relations with Russia," he said. "How can we not welcome this? Of course we welcome this."
And he was unfazed by Mr Trump's recently proposed ban on Muslims entering the US, which sparked condemnation from several world leaders.
Mr Putin said "his phrases that he uses to increase his popularity" was not of Russia's concern.
"It is not our business to rate this part of his work," he added.
Mr Trump, who leads the polls six weeks before Republican primary contests begin, has yet to respond to Mr Putin's praise.