Moscow(CNN) Russian President Vladimir Putin said Thursday that his US counterpart Donald Trump had made some "fairly serious achievements" since he took office and derided what he called the "espionage mania" surrounding meetings held by Trump associates with Russian officials.
The Trump administration has been embroiled for months in investigations into potential collusion between Russian operatives and Trump associates during the 2016 US presidential campaign and transition -- a claim Trump fiercely denies.
Asked for his assessment of Trump's first year in office during his annual end-of-year press conference in Moscow, Putin said that "objectively we can see a number of fairly serious achievements over the short period he's been working."
He cited the strength of the markets as an example, saying this indicated "investor confidence in the American economy, which means that they trust what President Trump is doing in this area."
Putin also dismissed the US investigations into potential collusion, saying it was normal practice for governments to meet with officials from other election campaigns as well as governments. He said the issue had been "dreamed up" by Trump's opponents in an effort to discredit him.
"It's delirium, it's madness," he said. "This is all dreamed up by people who are in the opposition to Trump so as to make sure that everyone thinks that what he's doing and working at is illegitimate."
Putin suggested that those supporting the inquiries were "working against the interests of their own country and against the duly elected President of the country."
In terms of Trump's foreign policy, Putin said there had been improvements in relations with Russia, but that it was obvious he was working under some constraints and limitations.
US and Russian citizens face common challenges, including terrorism, environmental issues, battling the proliferation of weapons of mass destruction, the Middle East and tensions on the Korean Peninsula, he said.
Putin accused the United States of provoking North Korea and called on both sides to deescalate the situation.
"I don't want to offend anybody but far as North Korea is concerned, we believe that what is happening now is counterproductive," Putin said.
Russia regularly warns the US against provoking North Korea with its joint military exercises with South Korea, Putin said, adding that it only takes one launch to create "catastrophic consequences."
He also said Russia does not accept North Korea as a nuclear state.
Asked whether the New Start nuclear arms treaty with the United States would survive, Putin laid responsibility for its future on Washington.
"We did not get out of the basic treaties that were the cornerstone of international security. We did not withdraw from the ABM Treaty, the United States withdrew unilaterally," he said, referring to the now defunct Anti-Ballistic Missile Treaty, from which the US withdrew in 2002.
Putin argued that while the United States was trying to accuse Russia of undermining the New Start treaty, it was itself doing just that with its deployment of anti-missile systems in Europe.
The New Start agreement, which went into effect in 2011, aims to cut the number of nuclear weapons that the US and Russia can deploy by about a third. The current version of the treaty is set to expire in 2021 and gives both countries until February 2018 to aim for a maximum of 700 deployed ICBMs, submarines and bombers, and a total of 1,500 warheads.
According to a report by Reuters, Trump criticized the New Start treaty in his first phone call with Putin after taking office, saying it favored Moscow.
Putin also said he expects military spending next year to reach 2.8 trillion roubles (about $47.7 billion) and added that the United States spends much more on its military than Russia does.
On the subject of domestic politics, Putin said he was planning to run as an independent in the 2018 presidential election -- his fourth presidential bid -- so that he can gain the support of multiple political parties who "support" his views.
He said his aim was for Russia to have a "competitive" and "balanced" political system but that it was not his responsibility to create his own opponents.
He said Russia should be as competitive politically as it is economically. "I want this and I will strive for a balanced political system and that is impossible without competition in the political field," he said.
Asked why Russia had no effective opposition figures, Putin said that most of current opposition figures were focusing on "making noise" rather than a genuine agenda that can benefit the nation and compete with those in power.
Many young Russians don't remember the problems the nation faced in the 1990s and early 2000s, he added.
Asked about the doping scandal that has engulfed areas of Russian sport, Putin said it was being exaggerated in the run-up to Russia's 2018 presidential election but acknowledged that "we have been responsible for it to some extent."
"We have used doping but other countries have also done it," he said.
Despite the "media storm" around Russian doping, there are other "systemic" issues in the sports world that must be looked at, Putin said. He added that Russia had to "help our sportsmen to help themselves."
Asked a follow-up question about state-sponsored doping and evidence provided by whistleblower Grigory Rodchenkov, Putin cast doubt on his credibility and even implied that the FBI, the United States' domestic intelligence and law enforcement agency, was drugging him.
"The fact that [Rodchenkov] is under control and protection of the FBI, that is not a plus to us, this is a minus. It means that he works under the control of American intelligence, what are they doing to him there? What substances is he given to say what has to be said? This is just funny."
Putin added that he had "great respect" for international sporting organizations and anti-doping bodies and that Russia understood it was "not easy for them" to work under pressure. But, he said, they must base their conclusions "on something objective."