White House press secretary Sarah Huckabee Sanders said in a statement that the mission to eradicate Islamic State fighters in Syria is "coming to a rapid end."

But she said the U.S. remains committed to seeing that mission through. "We will continue to consult with our allies and friends regarding future plans. We expect countries in the region and beyond, plus the United Nations, to work toward peace and ensure that ISIS never re-emerges," she said.

The statement seemed intended to thread a needle in the delicate diplomacy underlying the counter-terrorism mission in the Middle East: Letting allies know that the U.S. won't abandon them — but also prodding them to prepare for what happens when the mission is completed.

The White House sees Saudi Arabia as a key player. Trump spoke with King Salman bin Abdulaziz Al Saud Tuesday, seeking to ensure that Iran doesn't fill the void left by the Islamic State's defeat.

Trump met Tuesday with Defense Secretary Jim Mattis and Gen. Joseph Dunford, the chairman of the Joint Chiefs of Staff, to hash out a Syria strategy now that the Pentagon estimates that 90% of Islamic State fighters have been killed.

Trump, who has pointedly refused to set withdrawal dates for U.S. forces in Afghanistan and Iraq, is also not setting a withdrawal date for Syria. There are about 2,000 U.S. troops in Syria, working as advisers to the Syrian Defense Forces.

But Trump has also made clear that he will not accept mission creep, and does not want a nation-building effort in northeastern Syria and northwestern Iraq. the Syrian civil war and the aftermath of the Iraq War has led to a vacuum that provided fertile territory for terrorist groups attempting to establish a so-called caliphate.

"I want to start rebuilding our nation. We will have, as of three months ago, $7 trillion in the Middle East over the last 17 years. We get nothing — nothing out of it, nothing," Trump said Tuesday. "I want to rebuild our nation."