U.S. Defense Secretary Ash Carter made an unannounced visit to Afghanistan on Friday, amid questions about what President-elect Donald Trump’s foreign policy will mean for the country as it faces a renewed Taliban-led insurgency.

Carter will meet U.S. troops and Afghan President Ashraf Ghani while in Afghanistan.

Trump has given few details on his foreign policy plan, with surprisingly little specifics on Afghanistan, where nearly 10,000 U.S. troops still remain more than 15 years after the Islamist Taliban were toppled by U.S.-backed Afghan forces.

Afghanistan was barely mentioned during a bitterly fought election campaign, which largely focused on domestic issues, between Republican Trump and his Democratic rival, former secretary of state Hillary Clinton.

Trump, however has said the United States should stop carrying out “nation building.”

Ghani and Trump spoke by telephone last week, the Trump transition team said in a statement, when they discussed the “terrorism threats facing both countries.”

One of the most important questions on Afghanistan facing Trump, former officials and experts say, is how many U.S. troops will remain there.

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