President Donald Trump is expected to deliver a "major statement" Sunday, the White House announced late Saturday.

White House deputy press secretary Hogan Gidley said Trump will address the nation Sunday at 9 a.m. ET from 1600 Pennsylvania Ave. It wasn't immediately clear what the president will discuss in his speech.

The scheduled announcement comes after Trump teased his Twitter followers that: "Something very big has just happened!"

Syria conflict: Trump declares 'big success,' lifts sanctions on Turkey

Citing a senior US defense official, CNN reported that the U.S. military targeted Islamic State leader Abu Bakr al-Baghdadi in a raid in northwest Syria on Saturday. Trump approved the mission nearly a week before it took place, Newsweek reported.

In April, the Islamic State, also known as ISIS, released a video purportedly showing Baghdadi for the first time in nearly five years. According to the Associated Press, he presided over the Islamic State's ascendancy as it cultivated a reputation for beheadings and attracted hundreds of thousands of followers to a sprawling and self-styled caliphate in Iraq and Syria.

Baghdadi remained among the few ISIS commanders still at large despite multiple claims in recent years about his death and even as his so-called caliphate dramatically shrank, with many supporters who joined the cause either imprisoned or jailed.

Saturday's strike came amid concerns that a recent American pullback from northeastern Syria could infuse new strength into the militant group, which had lost vast stretches of territory it had once controlled.

Sen. Duckworth: With Syria drawdown, Donald Trump turns his back on America's credibility

Contributing: Associated Press

This article originally appeared on USA TODAY: President Trump to make 'major statement' Sunday after cryptic tweet