The more contagious variant of coronavirus that originated in the UK, the B-117 variant, has become the dominant strain in the U.S., CDC director Rochelle Walensky said on Wednesday.

"Based on our most recent estimates from CDC surveillance, the B-117 variant is now the most common lineage circulating in the United States," Walensky told reporters at a White House briefing.

Walensky’s comment was on schedule with previous predictions that the B-117 variant would become the more dominant strain by late March or early April.

Walensky did not specify on Wednesday just how dominant the B-117 variant is, but a spokesperson at the CDC said she was referring to preliminary data that has not yet been released but shows B-117 is the most dominant strain.

That tracks with the latest available CDC data on cases through March 13, which shows the percentage of B-117 cases more than doubled from late February to mid-March.