Facebook looks as if it's preparing for war with US President Donald Trump.

The company recently hired Kate Patchen, the chief of the Department of Justice's antitrust division in San Francisco.

It follows Trump saying that his administration is "looking at" antitrust proceedings against Google, Amazon, and Facebook.

Facebook is also hiring a lead counsel on competition matters in Washington.

Facebook has hired one of the top antitrust lawyers in Silicon Valley in a sign that the company could be preparing for war with Donald Trump's administration.

Kate Patchen, the chief of the Department of Justice's antitrust division in San Francisco, has joined Facebook as director and associate general counsel of litigation.

Patchen updated her LinkedIn profile earlier this month with the news, which was first spotted by the Financial Times. Business Insider has contacted Patchen and Facebook for comment.

Patchen's hire comes during the same month that US President Donald Trump said his administration was "looking at" antitrust proceedings against tech giants Google, Amazon, and Facebook.

"You look at the European Union, they fined I guess it was Google, billions of dollars, and frankly I don't like that they're doing that because that's an American company," Trump told Axios. "I don't think it's good that they're doing that. But if anybody does that, it should be us doing it."

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Patchen has worked at the Department of Justice for 14 years, during which time she has prosecuted a number of price-fixing cartel cases in the computer-memory-chip industry.

Her appointment is not the only sign that Facebook is beefing up its legal bench amid the threat of hostilities from the White House.

Facebook is also looking to hire a lead counsel on competition matters in Washington. In an ad on LinkedIn, it said the successful candidate would "Manage investigations and inquiries related to antitrust matters and help develop the company's legal position and strategy on competition matters throughout the world."