U.S. officials have confirmed to CBS News that plans have been approved for a series of strikes over a number of days against targets — including Iranian personnel and facilities — inside Iraq and Syria. The strikes will come in response to drone and rocket attacks targeting U.S. forces in the region, including the drone attack on Sunday that killed three U.S. service members at the Tower 22 base inside Jordan, near the Syrian border.

Speaking at the Pentagon Thursday, Defense Secretary Lloyd Austin told reporters that the U.S. won't tolerate attacks on American troops.

"This is a dangerous moment in the Middle East," Austin said, noting that Israel's ongoing war against Hamas in the Gaza Strip and attacks by Houthi rebels in Yemen on commercial shipping in the Red Sea were also happening in the region. "We will continue to work to avoid a wider conflict in the region, but we will take all necessary actions to defend the United States, our interests and our people, and we will respond when we choose, where we choose and how we choose."

Weather will be a major factor in the timing of the strikes, the U.S. officials told CBS News, as the U.S. has the capability to carry out strikes in bad weather but prefers to have better visibility of selected targets as a safeguard against inadvertently hitting civilians who might stray into the area at the last moment.