U.S. Vice President Kamala Harris will talk to major Democratic donors on Friday, according to a source familiar with the call, after President Joe Biden said he planned to return to the campaign trail next week even as more lawmakers called for him to step aside.

“She’s doing the call at the direct request of senior advisers to the president,” the person said.

The call was first reported by The New York Times, which said it was not immediately clear what message Harris planned to deliver to the network of donors on the 30-minute call that was arranged on short notice.