The World Health Organization (WHO) chief has rejected as false allegation from U.S. Secretary of State Mike Pompeo that he owed his position to a deal with China.

Director-General Dr. Tedros Adhanom Ghebreyesus, who was appointed on July 1, 2017, has been accused by U.S. President Donald Trump and Pompeo of being pro-China during the fight against the coronavirus. 

"The comments are untrue and unacceptable and without any foundation, for that matter," Tedros said in response to a question raised at WHO's Geneva headquarters briefing about remarks by Pompeo reported in London on Tuesday. 

"Our sole focus – and the focus of the entire organization – is on saving lives. ... And WHO will not be distracted by these comments. We don't want the international community also to be distracted."

A WHO advance team has been in China for nearly two weeks, organizing a WHO-led international mission to investigate the origins of the virus. The outbreak was first reported in a market in the central city of Wuhan late last year. 

"We are already beginning to reach out to experts at the international level to see who will be available and most appropriate to be able to support an international mission in the coming weeks," said Mike Ryan, WHO's top emergencies expert. 

U.S. adminstration under President Donald Trump has gone ahead to severe ties with the global health agency. 

In May, WHO said it will initiate an independent review into its handling of the coronavirus pandemic "at the earliest appropriate moment" and urged countries to continue funding the agency. 

Half of all cases are from U.S., Brazil and India

Tedros added the WHO was seeing intense transmission of the coronavirus in relatively few countries. 

"Two-thirds of all cases are from 10 countries. Almost half of all cases reported so far are from just three countries," he said, referring to the U.S., Brazil and India. 

Worldwide, more than 15 million cases and nearly 620,000 deaths have been reported, he said. 

Recorded U.S. coronavirus infections exceeded four million on Thursday, with more than 2,600 new cases per hour on average, the highest rate in the world, according to a Reuters tally. 

Infections in the U.S. have rapidly accelerated since the first COVID-19 case was detected on January 21. It took the country 98 days to reach one million cases, another 43 days to reach two million and then 27 more days to reach three million. 

It has only taken 16 days to reach four million, at a rate of 43 new cases a minute. 

Tedros said that just because cases may be at a low level where someone lives, it doesn't mean they should let down their guard. 

"Know your situation – do you know how many cases were reported where you live yesterday? Do you know how to find that information? Do you know how to minimize your exposure?" he said.

(With input from Reuters)