New York celebrated with fireworks as the reaching of a vaccination milestone meant that Covid-19 restrictions could be relaxed in the state.

Governor Andrew Cuomo confirmed on Tuesday that 70% of adults in New York have received at least one dose of a coronavirus vaccine, a threshold he said the state would celebrate

The fireworks were set off on Tuesday night on a barge moored near to the Statue of Liberty.

There were other fireworks displays around the state to celebrate and honour essential workers.

Cuomo said: "What does 70% mean? It means that we can now return to life as we know it."

Effective immediately, he said, the state is lifting rules that required many types of businesses to follow cleaning protocols or take people's temperatures or screen them for recent COVID-19 symptoms.

Movie theatres will no longer have to leave empty seats between patrons. Restaurants will no longer be forced to sit parties at least six feet apart.

Stores will not have to limit how many customers they admit. New York had previously allowed businesses to stop enforcing social distancing and mask rules for vaccinated patrons.

Some rules will remain: New Yorkers, for now, will continue to have to wear masks in schools, subways, large sports arenas, homeless shelters, hospitals, nursing homes, jails and prisons.

Unvaccinated New Yorkers will still be subject to a mask mandate while indoors in public places.

Cuomo said New York would remember Tuesday, June 15 - also the birthdate of his late father, the former governor Mario Cuomo - as the date when New York "rose again."

It's unclear how many more people have to get vaccinated to reach herd immunity from the coronavirus, which is when so many people are resistant to the virus that it has trouble spreading.

Many experts say it's 70% or higher. So far, about 50 percent of New Yorkers, of all ages, are fully vaccinated, according to federal data.

Dr Anna Bershteyn, professor of population health at the New York University Grossman School of Medicine, said the rise of more contagious variants could mean that as much as 85% of the population will need to be vaccinated for herd immunity.

She urged the public to keep avoiding crowded, poorly ventilated indoor spaces in less-vaccinated communities.

"It's the unvaccinated people sharing air in a stuffy space that really is the dangerous situation where a superspreading event can easily happen," Bershteyn said.

Since Jan. 1, about 1.1 million people have tested positive for the coronavirus in New York, according to state data, but new infections have plummeted this spring.

Over the past seven days, New York has been averaging around 430 new coronavirus cases a day, the lowest recorded level since the pandemic began. Fewer than 620 virus patients were hospitalised, the lowest level since late August.

The pace of vaccinations has slowed substantially. New York administered nearly 582,000 doses over the past seven days, down from a one-time average of one million doses each week.