The United States asked china on Tuesday to step up its cooperation with international health authorities over the outbreak of a deadly virus that has claimed more than 100 lives.

“We are urging China — more cooperation and transparency are the most important steps you can take toward a more effective response,” Health and Human Services Secretary Alex Azar told reporters.

He added that the United States has offered China assistance three times so far without success.

“On January the sixth, we offered to send a CDC team to China that could assist with these public health efforts,” said Azar.

“I reiterated that offer when I spoke to China’s minister of health on Monday, and it was reiterated again via the world Health Organization’s leadership today in Beijing.”

US Asks China For 'More Cooperation And Transparency' On Virus Passengers wear masks to protect against the spread of the Coronavirus as they arrive at the Los Angeles International Airport photo: AFP / Mark RALSTON

China was quick to sequence the genome of the 2019 Novel Coronavirus and make it public, allowing scientists around the world to develop diagnostic tools and winning praise for its efforts, including from US President Donald Trump.

But the new revelation by Azar raises questions about how much China has cooperated since then.

China was severely criticized for its handling of the SARS epidemic of 2002-2003.

“CDC experts are standing by ready, willing and able to go immediately to China, either on a bilateral basis or under the auspices of the World Health Organization,” continued Azar.

This would be necessary so that “we can see raw data, raw evidence and help design the types of studies and analytics” to answer critical questions such as incubation period.