President Donald Trump’s top trade adviser, Peter Navarro, mocked the Chinese government after it went after him for inventing a fake expert to bash Beijing in a number of his books.

It was found out earlier this month that a Harvard-educated China hawk and investor Navarro had cited, Ron Vara, was in fact just an anagram of Navarro’s name. Vara is quoted in several of Navarro’s books, and he’s said some pretty nasty things about China.

In “Death by China,” a 2011 Navarro book, Vara was quoted as saying “only the Chinese can turn a leather sofa into an acid bath, a baby crib into a lethal weapon, and a cellphone battery into heart-piercing shrapnel.”

Navarro has admitted to inventing the Vara character, calling it a “whimsical device and pen name,” more of an inside joke he knew people eventually would catch on to.

China, however, took exception to Navarro’s “lies,” saying they “threaten and undermine international relations and order.”

Navarro is of course working on a new trade deal with China, and he has reportedly been one of the central figures in Trump‘s ear about raising tariffs on Chinese imports. Beijing can’t be happy about the revelations concerning the Vara character.

“Frankly, this case triggered strong responses and astonishment worldwide,” Chinese Foreign Ministry spokesperson Hua Chunying said. “On some level, it shows that out of personal or political hidden intentions, certain people in the U.S. can do whatever they can think of to contain and smear China without scruple.

“It is absurd and extremely dangerous to make lies, spread lies and even formulate policies based on lies. Such moves will threaten and undermine normal international relations and order. Apart from that, the U.S. will hurt its own interests in the end.”

Navarro was quick to fire back, mocking China and the country’s social credit system, which rewards or penalizes citizens based on their behavior, on CNN.

“A source close to Ron Vara indicates China has revoked his visa and lowered his social credit score. In a related event, the Ministry of State Security has banned all anagrams and humor in social media and nonfiction books.”

Editor’s note: Is it wise for the top trade adviser to mock China while the two sides are working on deal? Share your thoughts below.