Trump did not specify when Giuliani tested positive or if he was experiencing symptoms.
“Rudy Giuliani, by far the greatest mayor in the history of NYC, and who has been working tirelessly exposing the most corrupt election (by far!) in the history of the USA, has tested positive for the China Virus,” Trump tweeted, using a racist term for the coronavirus.
“Get better soon Rudy, we will carry on!!!”
Giuliani has been traveling frequently in the aftermath of the election, and often appears in public without a mask.
Last week, he appeared maskless before state lawmakers in Michigan, to challenge votes in the state. On Thursday, he spoke at the Georgia capitol building in a crowded legislative session, again without a mask.
Trump himself contracted Covid-19 in October, spending three days in hospital near Washington DC.
At least 40 people in the president’s orbit have tested positive since late September, including first lady Melania Trump, her son Barron, Donald Trump Jr, and senior aides and Republican politicians.