Jen Psaki, the White House Press Secretary, confirmed on Twitter Tuesday afternoon that she has tested positive for COVID-19 and will not take part in Joe Biden’s “historic” trip to Brussels.

“Today, in preparation for travel to Europe, I took a PCR test this morning. That test came back positive, which means I will be adhering to CDC guidance and no longer be traveling on the President’s trip to Europe,” posted Psaki.

“I had two socially-distanced meetings with the President yesterday, and he is not considered a close contact as defined by CDC guidance. I am sharing the news of my positive test today out of an abundance of transparency. The President tested negative today via PCR test,” she explained.

“Thanks to the vaccine, I have only experienced mild symptoms,” she added. “In alignment with White House COVID-19 protocols, I will work from home and plan to return to work in person at the conclusion of a five-day isolation period and a negative test.”

This is a developing story. Check back for updates.