"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!" Trump wrote on Twitter.
"How low has President Obama gone to tapp (sic) my phones during the very sacred election process. This is Nixon/Watergate. Bad (or sick) guy!," he wrote in another tweet, AFP reported.
An avalanche of new revelations about ties between Donald Trump's aides and Russia forced the White House back on the offensive Friday, overshadowing a presidential weekend trip to Florida and his well-received major speech.
Before arriving at his Mar-a-Lago resort for the fourth time in five weeks, Trump accused his political foes of conducting "a total witch hunt" into links with Moscow, which he denies.
The angry accusation came as Attorney General Jeff Sessions — a close Trump confidant and the US government's top law enforcement official — was forced to recuse himself from any Russia-related inquiries.