WASHINGTON, Aug 1 (Reuters) - U.S. President Donald Trump said on Wednesday that Attorney General Jeff Sessions should end a federal investigation into Russian interference in the 2016 election, drawing a rebuke from both Democrats and his fellow Republicans in Congress.
The Republican president has long complained about the criminal probe into his White House victory but Wednesday's comment appeared to be his most direct call for shutting down Special Counsel Robert Mueller's investigation.
In a series of tweets, Trump called it a "TOTAL HOAX" the idea his campaign worked with Moscow. "This is a terrible situation and Attorney General Jeff Sessions should stop this Rigged Witch Hunt right now, before it continues to stain our country any further," he said.
The White House said the tweet was not an order to Sessions and that Trump was expressing his frustration with the length of the probe.
Trump also said that Mueller is "totally conflicted." He provided no evidence that the team led by Mueller, a Republican who was appointed by a Republican, is biased against him.
The first trial arising from the probe into Russia's role in the election, began on Tuesday in Alexandria, Virginia. Trump's former campaign chairman, Paul Manafort, faces 18 counts of bank and tax fraud charges.
A Justice Department spokeswoman said the department had no immediate comment on Trump's tweet about ending Mueller's probe.
"It's not an order. It's the president's opinion," White House spokeswoman Sarah Sanders told a news briefing when asked about the tweet. She denied that Trump was obstructing the probe. "He's fighting back," she said.
Trump's personal lawyer, Rudy Giuliani, said that in his tweet Trump was expressing an opinion long espoused by his team.
"We have been saying for months that it is time to bring this inquiry to an end. The president has expressed the same opinion," Giuliani told Reuters.
Trump has steadily attacked Sessions for recusing himself from the Russia probe in March 2017. Sessions cited his role as a senior adviser to Trump's presidential campaign and appointed Deputy Attorney General Rod Rosenstein to oversee the investigation.
Rosenstein in turn appointed Mueller and is the person with the authority to fire him.
Mueller, a Republican and former FBI director who served a Republican and Democratic president, has broad support in Congress, where Trump's fellow Republicans control both chambers.
Six Republican senators going into a vote on Wednesday disapproved of Trump's tweet calling for an end to the probe.
"They ought to let them conclude their work. What they’re doing is something that is important and we support and I don’t think any effort to truncate that or somehow shut it down early is in the public’s best interest," said Senator John Thune, a junior member of the Senate's Republican leadership.
Senator Orrin Hatch said he did not think Sessions had the power to end the probe and it would be unwise to do so.
An element of Mueller's investigation includes whether Trump or anyone in the campaign tried to obstruct justice. The New York Times reported last week that the Mueller team was examining negative tweets and statements by Trump about Sessions and former FBI Director James Comey. Trump fired Comey in May 2017.
U.S. intelligence agencies concluded last year that Moscow meddled in the 2016 presidential campaign to try to tip the vote in Trump's favor. Moscow has denied such interference, and Trump has denied any collusion by his campaign or any obstruction of justice.
Democratic lawmakers said the tweet was an effort by Trump to end the probe.
"It's clear to me he's very worried about it and he wants to prevent it any way he can," said Senator Dianne Feinstein, the top Democrat on the Judiciary Committee.
"He's panicking," Democratic Representative Don Beyer said on Twitter. "Congress must protect Mueller."
In April, the Senate Judiciary Committee approved legislation to protect Mueller but Republican leader Mitch McConnell said there was no need to advance the bill because he did not believe Trump would fire Mueller.
Some legal analysts said Wednesday's tweet alone was not enough to bring an obstruction of justice charge but it could be used to establish a pattern of conduct revealing Trump's intentions.
"It is a piece of evidence. It is part and parcel with the other 94 things the man has done that show obstruction of justice," said Paul Rosenzweig, a former prosecutor who was part of a team that investigated President Bill Clinton. "But it is probably number 67, or number 72, on that list."
Jens David Ohlin, a law professor at Cornell University, said the tweets would likely not be seen as an order to Sessions, but as "Trump venting his continued frustration with the fact that he can't control the Russia investigation."
"But I do think it would be a piece of evidence in the obstruction case going back to the firing of Comey because it shows Trump has this intense desire to shut down the Russia investigation," he said.
Mueller's team has indicted or secured guilty pleas from 32 people and three companies, including the indictment of 12 Russian intelligence officials.
(Reporting by Doina Chiacu and Susan Cornwell Additional reporting by Karen Freifeld, Jan Wolfe and Susan Heavey Editing by Frances Kerry and Grant McCool)