"This report is a very important beginning, but it is not the end," said the WHO Director-General in his remarks on Tuesday.
"We have not yet found the source of the virus, and we must continue to follow the science and leave no stone unturned as we do," the WHO Chief added.
He welcomed the findings of the 34-member team, which in January, visited the Chinese city of Wuhan where the first cases of the then new coronavirus came to light at the end of 2019.
He noted that although much data had been provided, to fully understand the earliest cases, they would need access from Chinese authorities to data including biological samples from at least September 2019.
"In my discussions with the team, they expressed the difficulties they encountered in accessing raw data. I expect future collaborative studies to include more timely and comprehensive data sharing," he stated.
"I welcome the recommendations for further research, including a full analysis of the trade in animals and products in markets across Wuhan, particularly those linked to early human cases," he said.
According to Tedros, as far as WHO is concerned all hypotheses remain on the table.
Although the team has concluded that a laboratory leak is the least likely hypothesis, this requires further investigation, potentially with additional missions involving specialist experts.