WASHINGTON (AP) — A federal judge is warning President Donald Trump’s former campaign chairman that he shouldn’t be trying his case in the press. That includes drafting opinion essays published in other countries.

U.S. District Judge Amy Berman Jackson told Paul Manafort that his editing of an op-ed that appeared in an English-language newspaper in Ukraine is not something she is going to tolerate.

The judge’s warning came after special counsel Robert Mueller’s prosecutors discovered that Manafort edited an op-ed published in the Kyiv Post last week. The article appeared under the name of a former Ukraine official. It discussed Manafort’s consulting work in Ukraine, which is at the heart of the case against him.

The judge has barred Manafort and the prosecution from making public statements about his case.