When Pat Shanahan, America’s acting defense secretary, started his new job on Wednesday, he made it clear to his staff what his chief focus would be: “China, China, China.”

The former Boeing executive, who was elevated from the number two Pentagon position to fill the shoes of departing chief Jim Mattis, assembled the top civilian officials at the Defense Department for a meeting.

A defense official said Shanahan told the Pentagon gathering that he is focused on the strategy that was developed and put in place under Mattis, a retired Marine general. It emphasizes the importance of great power competition with Russia and China, after America’s many years of fighting insurgent wars in the Middle East.

A defense official who attended the meeting said Shanahan had told colleagues a major concern would be China.

“While we are focused on ongoing operations, Acting Secretary Shanahan told the team to remember: ‘China, China, China’,” said the official, who spoke on condition of anonymity.

The Trump administration has had a troubled relationship with China. Like the Obama administration, President Donald Trump’s government is concerned about what it calls China’s militarization of disputed areas in the South China Sea and by its advances in high-tech weaponry.

As acting secretary, Shanahan, 56, has all the authority of a permanent secretary. It is now known whether Trump will nominate Shanahan as Mattis’s successor or will select someone else. Shanahan had been the deputy secretary since July 2017. He spent his entire career with Boeing and has no previous government experience.

Mattis handed in his resignation on December 20 after a series of policy disagreements with Trump, including the president’s shock decision – announced on Twitter – to withdraw troops from Syria. Mattis said he would stay until the end of February, but on December 23 Trump announced that Shanahan would take over January. 1, accelerating Mattis’s departure.

– with reporting by Associated Press and Agence France-Presse