Russian President Vladimir Putin told reporters during his annual end-of-year news conference that he welcomes calls by U.S. Republican presidential frontrunner Donald Trump for deeper relations with Russia. He says Trump is the man to watch. (Reuters)

Russian President Vladimir Putin found a moment Thursday during a wide-ranging news conference to offer a strong endorsement of Republican front-runner Donald Trump, calling the billionaire presidential candidate the “absolute leader in the presidential race.”

Putin consecrated a budding international bromance between the two men as he commented on the U.S. campaign for the White House, saying that Russia would work with “whomever the American voters choose” but expressing special praise for Trump.

Trump said in October that he would “get along very well” with Putin and applauded the Russian leader for his intervention against the Islamic State in Syria. But until Thursday, Trump’s praise had gone unreciprocated.

“He’s a very lively man, talented without doubt,” Putin said when journalists approached him after the news conference and asked about Trump. “He’s saying he wants to go to another level of relations — closer, deeper relations with Russia. How can we not welcome that? Of course we welcome that.”

It was a moment of levity during a more than three-hour news conference that touched on Russia’s battered economy, Russia’s intervention in Syria, tense relations with Turkey over the downing of a Russian warplane, and the smoldering conflict in Ukraine.

Republican presidential frontrunner Donald Trump has said a lot of nice things about Russian president Vladimir Putin. Putin finally responded on Dec. 17. (Gillian Brockell/The Washington Post)

During the news conference, Putin denied once again that regular Russian forces were in Ukraine, where pro-Moscow rebels began clashes with the Western-backed government in 2014. But Putin hinted that Russian military advisers or security forces were active in that country, an involvement that he and senior Russian officials have sharply denied in the past.

“We never said that we did not have people there who are dealing with certain issues,” Putin said of southeastern Ukraine, the base for the Russian-backed separatists. “But there are no regular Russian troops there. Feel the difference!”

Putin’s statement came after a Ukrainian journalist “passed on a hello from Captain Erofeyev and Sergeant Alexandrov,” two alleged Russian servicemen captured by Ukrainian government forces. Russia has said they quit the army before going to Ukraine.

The format of the yearly news conference is a spectacle in itself: Nearly 1,400 journalists jostle on national television for the opportunity to ask Putin a question.

Putin answers in monologues that can stretch as long as 10 minutes, making it difficult for reporters to follow up.

Asked about Russia’s intervention in the civil war in Syria, Putin said Russian forces would remain there at least until a democratic process is launched.

“There is a plan,” Putin said. “In its key aspects, it coincides with the American plan: working on the constitution, preparing elections in Syria and the recognition of their results. But for now we are going to launch strikes and support the Syrian army in its offensive.”

But the United States and Russia differ sharply over Syrian President Bashar al-Assad. Washington and its allies insist that Assad has no role in Syria’s political future. Russia and Iran, however, are key backers of Assad and will likely resist any outcome that lessens their influence in Syria.

Russia began airstrikes to back Assad in September, but recently Russian analysts and government officials have expressed frustration with the slow speed of the offensive and ineffectiveness of the Syrian troops.

In a closed-door meeting before parliament on Wednesday, Russian Defense Minister Sergei Shoigu declined to put a time limit on the intervention but said that Russia “can’t count on a quick conclusion to the operation,” the RIA Novosti state news agency reported.

A day earlier, Putin met with Secretary of State John F. Kerry, striking an agreement to hold talks Friday in New York on a political settlement that may then be formalized in a United Nations resolution.

Putin largely reiterated Russia’s anger over the downing of one of its warplanes by Turkish jets last month.

“Life has shown that it is difficult for us, practically impossible, to come to terms with the incumbent Turkish administration,” Putin said. “Even when and where we say that we agree, they stab us in the side or in the back, for absolutely unclear reasons.”

He said that someone in the Turkish government may have ordered the attack on the Russian plane in an effort to please the United States, or as he put it, to “lick the Americans in a particular place.”

Putin also addressed Russia’s economy, which has been hit with high inflation and plunged against the dollar and euro as the price of oil has fallen drastically in recent months. While the dollar was worth 35 rubles two years ago, it now trades at more than 70 rubles.

Putin said that he was satisfied with the leadership of Russia’s government and the Central Bank, which steeply hiked interest rates to prevent inflation, despite the pain that the move has dealt to businesses and borrowers. He said he wanted to lower interest rates but that this would happen only when Russia could do so “in a natural way.”

Putin predicted that Russia would have 0.7 percent growth in 2016, 1.9 percent growth in 2017 and 2.4 percent growth in 2018. But he made those predictions with oil trading at $50 a barrel. Brent crude was trading at just over $37 a barrel on Thursday.

In a personal moment, Putin was asked about the identity of his daughters, after a series of investigations in the Russian press revealed that a woman named Katerina Tikhonova had attained a prominent position overseeing millions of dollars in investment at a high-tech business incubator at Moscow State University.

“They don’t engage in business, and they don’t engage in politics,” Putin said, declining to say whether Tikhonova was his daughter. “They are never going to get involved in that.”

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