New York City mayor Bill de Blasio, on Wednesday, said that the city will require the public hospital workers to get vaccinated or take a weekly coronavirus test as it faces a steep rise of cases due to the Delta variant.

The order will come into effect from August 2 and will be applied to around 30,000 employees in New York city's 11 public hospitals.

"This is the first step -- everyone should do this now to save lives," de Blasio told a press conference.

"If we don't see vaccination numbers go up fast enough, if we don't see progress against the variant, we are going to consider a range of options," he said.

He also added that he is hopeful that the private hospitals will be taking similar steps to curb the spread of the virus and protect the health workers.

The requirement is the most stringent measure taken in the US megacity where nearly 58% of the population has had at least one dose of a vaccine against COVID-19. This is a figure reached through a vaccination campaign that was based on voluntary participation and incentives.

While health care workers retain the option of being tested for the coronavirus weekly in place of getting vaccinated, de Blasio said he was confident people would choose to get a shot.

"I don't have a doubt in my mind this is going to move people towards vaccination."

The announcement comes as controversy builds in the United States over what steps should be taken to increase vaccination rates against the Delta variant, which accounts for 83% of US infections, according to recent estimates, news agency AFP reported.

Due to the rising number of cases, many health authorities are pushing to make vaccination mandatory, at least for certain sections of the population.

But several Republican-led states have instead passed laws banning coercive measures, particularly in schools.