The openings of two COVID-19 vaccination sites that were set to open on Thursday are now being postponed because of supply shortages and shipment delays caused by snow and sleet across the country, Mayor Bill de Blasio announced Wednesday evening.

The vaccination sites at the Empire Outlets on Staten Island and at Martin Van Buren High School in Queens Village will remain empty Thursday, which was the day they were supposed to begin distributing the shots.

"I cannot be clearer: we have the infrastructure in place to deliver half a million doses per week. All that's missing is the supply to get it done," the mayor said in a statement. "We need our the pharmaceutical companies to step-up and give us the doses we need to vaccinate the people of our city. There is not a moment to waste."

This is now the second time that the Empire Outlets mass vaccination hub has had a delayed opening. Last month, its opening, along with the openings of mass sites at Yankee Stadium and Citi Field, was pushed back because of supply shortages. Both stadiums were able to open earlier this month.

At this time, there is no set date for when these sites can get up and running. Joseph Ferrara, an Empire Outlets developer, said in a tweet that a new opening date would be released within the next few days.

Once the Staten Island location can open, the shots will be given in an empty storefront next to iOptics and Jewelers on Fifth, seven days a week from 8 a.m. to 5 p.m. Only eligible Staten Islanders are able to book appointments at this site.

According to new city data, Staten Island and Manhattan currently lead in COVID-19 vaccination rates compared to the other boroughs.