U.S. President Donald Trump declared Monday, "I never worked for Russia," days after news reports suggested he might be beholden to Russia and President Vladimir Putin."I think it's a disgrace you even asked that question," Trump told a reporter who queried him about his ties to Russia outside the White House as he prepared to leave for New Orleans to speak at a farm convention.The New York Times reported over the weekend that Federal Bureau of Investigation officials started investigating whether Trump "was knowingly working for Russia or had unwittingly fallen under Moscow's influence" because of his behavior after he fired former FBI chief James Comey in May 2017. At the time, Comey was leading the investigation into Russian meddling in the 2016 U.S. presidential election. The Washington Post also reported in recent days that Trump has gone to extraordinary lengths to hide details of his conversations the five times he has met with Putin over the last two years.Both the investigation into Russian meddling, and the investigation into whether the U.S. president has been working for Russian interests are now overseen by Special Counsel Robert Mueller.While the president continues to forcefully criticize the FBI's handling of the investigation into his campaign, the man he nominated as his new attorney general says he supports letting the Special Counsel's Russia investigation finish its work. William Barr, who served as attorney general for two years in the early 1990s, said Monday that allowing the Special Counsel's probe to conclude is "vitally important" and he supports a public report of its findings. Barr is expected to appear in confirmation hearings before the Senate Judiciary Committee on Tuesday.Hiding details of Putin talks Trump said Monday he had nothing to hide from his private two hours of talks with Putin in July at their Helsinki summit, where only interpreters were in the room with the two leaders. He said among other issues, they talked about security for Israel and construction of a controversial natural gas pipeline from Russia to Germany. The Washington Post reported on details of the lengths Trump has gone to keep senior officials from learning about his talks with Putin. On one occasion, the newspaper said Trump took possession of the notes of his own interpreter and instructed the linguist to not discuss what had transpired with other Trump administration officials. The newspaper said that incident occurred after Trump and Putin met in Hamburg in 2017, a meeting also attended by then-U.S. Secretary of State Rex Tillerson.Trump has disparaged the newspaper reports, while characterizing himself as tough on Moscow.He told Fox News talk show host Jeanine Pirro on Saturday "if you ask the folks in Russia, I've been tougher on Russia than anybody else, any other -- probably any other president period, but certainly the last three or four presidents, modern day presidents."Asked directly whether he is now or has ever worked for Russia, he said, much as he did Monday, "I think it's the most insulting thing I've ever been asked."Trump said the Times's account of the mid-2017 FBI investigation of him was "a very horrible thing. They really are a disaster of a newspaper."Democrats concernedVirginia Senator Mark Warner, the leading Democrat on the Senate Intelligence Committee that has been investigating Trump campaign links with Russia, told CNN on Sunday that at times Trump has "almost parroted" Putin's policies."It's a very real consideration" whether Trump is a willing agent of Russia," Warner said, especially considering information that surfaced last week that former Trump campaign chairman Paul Manafort shared Trump campaign polling data in 2016 with a former business associate of his that U.S. investigators believe had ties to Russian intelligence.Another key Senate Democrat, Dick Durbin of Illinois, told ABC News there are "serious questions" about why Trump is "so chummy" with Putin.Earlier, House Judiciary Committee Chairman Jerrold Nadler said in a statement that in the coming weeks his panel "will take steps to better understand both the president's actions and the FBI's response to that behavior."Trump also assailed the Post's story, dismissing concerns about the secrecy surrounding his talks with Putin in Helsinki. No official accounts of their talks have been released, but Trump told Pirro there was nothing to hide about their discussions and could release a transcript."We had a great conversation," he said. "We were talking about Israel and securing Israel and lots of other things. And it was a great conversation. I'm not keeping anything under wraps, I couldn't care less. I mean, it's so ridiculous."He added, "Anybody could have listened to that meeting, that meeting is up for grabs."All-consuming Russia probeTrump's first two years in office have been consumed by the now 20-month investigation whether his 2016 campaign colluded with Russia to help him win and whether, as president, Trump obstructed justice by trying to thwart the probe by special counsel Robert Mueller, who took over the investigation after Trump ousted Comey.Shortly after Trump dismissed Comey, he told NBC news anchor Lester Holt he was thinking of "this Russia thing" when he decided to fire the FBI chief, saying he felt the investigation was created by Democrats dismayed that Trump had upset former U.S. Secretary of State Hillary Clinton to win the White House.Mueller is believed to be nearing the end of his investigation and is expected to write a report on his findings.