PORTLAND, Oregon: A coalition of 15 bars in Portland, Oregon have agreed to require proof of COVID-19 vaccinations for entry, as the delta variant is spreading throughout the state.

The coalition is being organized by Daniel Shoemaker, owner of the Teardrop Cocktail Lounge.

Some 30 other bars are expected to join in the coming days, as they aim to protect customers and staff by allowing entry to only vaccinated guests, Shoemaker said, according to the Associated Press.

Every bar in the coalition will decide on what constitutes as proof, though a vaccine card or photo card should suffice. Most bars will continue to offer outdoor seating to the entire public.

The new coalition was formed after hundreds of West Coast bars joined similar groups in San Francisco and Seattle last week, even as some are facing social media backlash.

However, Shoemaker expects his in-person customers to be mainly supportive. The vaccine ID requirement had been enforced during the summer at Teardrop's adjacent lounge, Crybaby.

Shoemaker and others are also monitoring New York City's preparations to begin enforcing its vaccine mandate for indoor activities at restaurants, gyms and theaters.