The UN agency said in a statement late Saturday that a German magazine's report about a telephone conversation between WHO chief Tedros Adhanom Ghebreyesus and Chinese President Xi Jinping on January 21 was "unfounded and untrue".
Weekly Der Spiegel reported that Xi asked Tedros during the call to hold back information about human-to-human transmission of the virus and delay declaring a pandemic.
The magazine quoted Germany's foreign intelligence agency, BND, which declined to comment on Sunday.
Der Spiegel also claimed that the BND concluded up to six weeks of time to fight the outbreak had been lost due to China's information policy.
The UN agency said Tedros and Xi "have never spoken by phone" and added that "such inaccurate reports distract and detract from WHO's and the world's efforts to end the COVID-19 pandemic."
It said that China confirmed human-to-human transmission of the new coronavirus on January 20.
WHO officials issued a statement two days later saying there was evidence of human-to-human transmission in Wuhan, but more investigation was necessary.
The global body declared COVID-19 a pandemic on February 11.
US President Donald Trump has been among the strongest critics of WHO's handling of the pandemic, accusing it of deference to China and ceasing payments to the agency. (AP) SCYSCY