President Joe Biden’s White House Pride Month event, which is projected to be the largest in history, will be moved from Thursday evening to Saturday, officials said, due to a cloud of smoke from Canadian wildfires.

“Today’s Pride event on the White House South Lawn has been rescheduled for Saturday due to anticipated air quality in the region,” the White House stated in a statement.

The party, which is expected to include thousands of guests on the White House’s South Lawn, is a deliberate contrast to a cascade of Republican legislation and other attacks targeting LGBTQ+ people, Biden officials have said.

Forest fires continued to burn across Canada on Thursday as the country endured its worst-ever start to wildfire season, sending a smoky haze billowing across U.S. cities and grounding flights.

Biden, a Democrat, planned an evening celebration of LGBTQ+ families featuring singer Betty Who and Baltimore DJ Queen HD.

He was also expected to announce new measures Thursday to help schools and LGBTQ kids navigate book bans, community centers fight threats, and transgender youth access better care, domestic policy adviser Neera Tanden said.

It wasn’t immediately clear whether those announcements would be postponed as well.

“This year we’re seeing a disturbing surge in violent threats against LGBTQ community organizations,” Tanden told reporters on a conference call Wednesday evening. “In too many parts of our country, LGBTQ Americans are being targeted for who they are, and that, simply put, is discrimination.”