WASHINGTON, May 19 (Xinhua) -- Domestic political pressure has mounted on U.S. President Donald Trump after former FBI director Robert Mueller's appointment as the special counsel to oversee a federal probe into his election campaign's relations with Russia.
On Thursday, Trump said the Justice Department appointment a day before was part of a "witch hunt" that "divides the country."
"I respect the move but the entire thing has been a witch hunt and there is no collusion between certainly myself and my campaign, but I can only speak for myself -- and the Russians. Zero," Trump said at a joint press conference with his Colombian counterpart Juan Manuel Santos in the White House.
The U.S. president tweeted Thursday morning branding the probe into an alleged Russian collusion with his campaign the "single greatest witch hunt" in political history.
"I believe it hurts our country terribly, because it shows we're a divided, mixed-up, not-unified country," Trump said later at a luncheon with a group of television news anchors.
However, Mueller's appointment has received wide bipartisan welcome across Congress.
Deputy Attorney General Rod Rosenstein said in a statement on Wednesday that the appointment "is necessary in order for the American people to have full confidence in the outcome" of the probe.
"My decision is not a finding that crimes have been committed or that any prosecution is warranted," said Rosenstein, who had been overseeing the Russia probe following the recusal of Attorney General Jeff Sessions due to his failure to disclose a meeting with Russian Ambassador Sergey Kislyak.
Mueller, who served as FBI director between September 2001 and September 2013, will have the authority to investigate whether the Russian government colluded with individuals associated with Trump's campaign and to prosecute federal crimes uncovered in the probe.
Democratic lawmakers have been clamoring for Rosenstein to appoint a special prosecutor in the wake of Tuesday's reports that James Comey, who was fired last week as director of Federal Bureau of Investigation (FBI), penned a memo documenting a request from Trump that he "let go" of the investigation into former National Security Advisor Michael Flynn.
During the White House press conference on Thursday, when asked whether he required Comey to shut down the probe into Flynn, Trump answered: "No. No. Next question."
In addition, Trump dismissed suggestions of criminal charges or impeachment, saying "I think it's totally ridiculous."
Though the Mueller appointment has obviously raised the legal and political stakes for Trump, it is widely thought that Trump is unlikely to be impeached over the current political turmoil.
"Unlike in the Watergate case, there is no evidence that the president ordered witnesses to lie, destroyed evidence or tried to block FBI agents from doing their job," said John Yoo, a law professor at the University of California, Berkeley.
Earlier, a Washington Post report on Monday said some Republican lawmakers are distancing themselves from Trump amid allegations that he shared sensitive intelligence with Russian Foreign Minister Sergey Lavrov during a White House meeting last week.
The accusation has met with vehement rejection by Trump, as well as by Lavrov.
On Thursday, during a working visit to Cyprus, Lavrov said what Trump actually told him was that Islamic State (IS) terrorists were capable of staffing untraceable explosives in laptops.
"As far as I can recall, maybe one month or two months before, the Trump administration had an official ban on laptops on airlines from seven Middle Eastern countries ... So if you are talking about that, I see no secret here," Lavrov told reporters in Nicosia during a joint news conference.
Lavrov's comments on the issue were the first since his meeting with Trump and after allegations were made by U.S. officials on May 15 that Trump had divulged secrets to Lavrov about planned IS operations.