President Joe Biden on Thursday said the U.S. will give high-quality masks to Americans for free, as new infections from the Covid-19 omicron variant soar across the country.

Biden said the U.S. has more than tripled the national stockpile of highly protective N95 masks to make sure they are widely available to the general public. He said masks are a crucial tool to help control the spread of omicron.

“I know that for some Americans, the mask is not always affordable or convenient to get,” Biden said in addressing the nation from the White House. “Next week we’ll announce how we’re making high-quality masks available to the American people for free.”

Sen. Bernie Sanders, I-Vt., reintroduced legislation on Wednesday to distribute free N95 masks to every person in the U.S. for free. Everybody would receive a package with three highly protective masks. Sanders’ legislation has 50 Democratic co-sponsors in the House and Senate.

“As we face the rapidly spreading omicron variant, we should remember that not all face masks are created equal,” Sanders said in a statement. “Congress must demand the mass production and distribution of N95 masks, one of the most effective ways to stop the spread of the Covid virus.”

Dr. Rochelle Walensky on Wednesday said the Centers for Disease Control and Prevention would soon update its masking guidance to inform Americans about the different levels of protection different masks provide. However, Walensky said the CDC recommends that any mask is better than no mask.

“We do encourage all Americans to wear a well-fitting mask to protect themselves and prevent the spread of Covid-19, and that recommendation is not going to change,” the CDC director said during a White House Covid update.

The CDC recommends that everyone, regardless of vaccination status, wear masks in indoors public spaces in areas with substantial or high virus transmission. Right now, virtually every county in the U.S. has high transmission of the virus, according to the agency. Omicron currently represents 98% of all sequenced Covid cases in the U.S., according to the CDC.

Researchers in Australia found that fabric masks are least 50% effective at filtering virus particles, while N95 and surgical masks are about 99% effective. The study was published in the peer-reviewed journal Pathogens in September 2020.