Washington: US President Donald Trump has launched extraordinary accusations against former president Barack Obama, accusing him of "wiretapping" Trump Tower during the US elections.
Trump issued the allegations in a series of early morning tweets on Saturday, but offered no evidence to support the allegation.
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Trump alleges wiretapping by Obama
Donald Trump accuses Barack Obama of wiretapping him during the late stages of the presidential election campaign, but offered no evidence to support the allegation.
"How low has President Obama gone to tapp my phones during the very sacred election process. This is Nixon/Watergate. Bad (or sick) guy!" Trump said.
A spokesperson for Obama denied the allegations in a statement: "A cardinal rule of the Obama Administration was that no White House official ever interfered with any independent investigation led by the Department of Justice.
"As part of that practice, neither President Obama nor any White House official ever ordered surveillance on any US citizen. Any suggestion otherwise is simply false."
The White House did not respond to a request to clarify Trump's tweets.
Officials at the Federal Bureau of Investigation and the Department of Justice declined to comment.
Trump has been feuding with the intelligence community since before he took office, convinced that career officers as well as holdovers from the Obama administration have been trying to sabotage his presidency.
He has ordered internal inquiries to find who leaked sensitive information regarding communications during the campaign between Russian officials and his campaign associates and allies, including Attorney-General Jeff Sessions and ousted national security adviser Michael Flynn.
In one of the tweets, Trump said the alleged wiretapping took place in his Trump Tower skyscraper in New York, but there was "nothing found".
It's the second time inside a week Trump has attacked his predecessor.
In an interview on Fox News on Monday, Trump accused Obama of orchestrating protests against his new administration.
On Saturday, Eric Swalwell, a Democrat who is a member of the House Intelligence Committee, downplayed Trump's allegation.
"I think this is just the President up early doing his routine tweeting," he told Fox News.
"Presidents don't wiretap anyone. These [wiretaps] are pursued by the Department of Justice in accordance with the FBI and signed off by a judge."
Ben Rhodes, Obama's former deputy national security adviser, denied Trump's claims.
No President can order a wiretap. Those restrictions were put in place to protect citizens from people like you. https://t.co/lEVscjkzSw
— Ben Rhodes (@brhodes) 4 March 2017
Some current and former intelligence officials also cast doubt on Trump's latest accusations, which appeared to in part resemble a report posted on the far-right Breitbart website on Friday.
"It's highly unlikely there was a wiretap on the president-elect," one former senior intelligence official, who requested anonymity to speak candidly, told The Washington Post.
"It seems unthinkable. If that were the case by some chance, that means that a federal judge would have found that there was either probably cause that he had committed a crime or was an agent of a foreign power."
A wiretap cannot be used at a US facility without finding probable cause that the phone lines or internet addresses were being used by agents of a foreign power – or by people spying for or acting on behalf of a foreign government.
"You can't just go around and tap buildings," the official said.
The Trump administration has come under pressure from FBI and congressional investigations into contacts between some members of his campaign team and Russian officials during his campaign.
Obama imposed sanctions on Russia and ordered Russian diplomats to leave the US in December over the country's involvement in hacking political groups in the November 8 presidential election.
Flynn resigned in February after revelations that he had discussed US sanctions on Russia with the Russian ambassador to the United States before Trump took office.
Flynn had promised Vice-President Mike Pence he had not discussed US sanctions with the Russians, but transcripts of intercepted communications, described by US officials, showed that the subject had come up in conversations between him and the Russian ambassador.
Trump has often used his Twitter account to attack rivals and for years led a campaign alleging that Obama was not born in the US.
Here are Trump's latest accusations in full.
Terrible! Just found out that Obama had my "wires tapped" in Trump Tower just before the victory. Nothing found. This is McCarthyism!
— Donald J. Trump (@realDonaldTrump) March 4, 2017
Just out: The same Russian Ambassador that met Jeff Sessions visited the Obama White House 22 times, and 4 times last year alone.
— Donald J. Trump (@realDonaldTrump) March 4, 2017
Is it legal for a sitting President to be "wire tapping" a race for president prior to an election? Turned down by court earlier. A NEW LOW!
— Donald J. Trump (@realDonaldTrump) March 4, 2017
I'd bet a good lawyer could make a great case out of the fact that President Obama was tapping my phones in October, just prior to Election!
— Donald J. Trump (@realDonaldTrump) March 4, 2017
How low has President Obama gone to tapp my phones during the very sacred election process. This is Nixon/Watergate. Bad (or sick) guy!
— Donald J. Trump (@realDonaldTrump) March 4, 2017
Reuters, The Washington Post