The head of the Federal Election Commission sent out a timely warning to politicians on Thursday, reminding them that it’s illegal to accept information from a foreign national linked to an election in the U.S.

The notice, posted by FEC Chair Ellen Weintraub, comes one day after President Donald Trump told ABC News﻿ that he would accept dirt on his opponents in the 2020 election from another country, such as Russia or China.

Weintraub’s warning was direct: “Let me make something 100% clear to the American public and anyone running for public office: It is illegal for any person to solicit, accept, or receive anything of value from a foreign national in connection with a U.S. election.”

“This is not a novel concept,” she added.

The chair posted the memo on Twitter, along with an expression of disbelief.

“I would not have thought that I needed to say this,” she tweeted.