Brazil's health regulator on Wednesday authorised the resumption of large-scale clinical trials on a potential coronavirus vaccine developed by a Chinese company just over a day after shutting the test down, according to AP.

The initial decision by Anvisa led to a storm of complaints that the action was more political than scientific.

The agency had cited an adverse, serious event that occurred on Oct. 29 as the reason for halting the trials on Monday night, but said Wednesday it now has sufficient elements to allow vaccination to resume.

The potential CoronaVac vaccine is being developed by Chinese biopharmaceutical firm Sinovac and in Brazil would be mostly produced by Sao Paulo's state-run Butantan Institute.