The U.S. military is prohibiting the travel of American troops to the West Bank — which includes Bethlehem and Jerusalem’s Old City — over security concerns following a Monday White House reversal of a decades old American policy that has viewed Israeli settlements in the territory as a violation of international law.

U.S. European Command was simply following State Department guidance on travel restrictions in Israel, said Lt. Cmdr. Joe Hontz, a spokesman for the command.

The EUCOM “policy applies to military personnel, DoD civilian employees, contractors and command-sponsored dependents and family members,” Hontz told Military Times in an emailed statement.

The U.S. Embassy in Israel released a travel warning Monday for Americans traveling to Jerusalem, the West Bank or Gaza, cautioning travelers to “maintain a high level of vigilance and take appropriate steps to increase their security awareness in light of the current environment.”

“Individuals and groups opposed to the Secretary of State’s recent announcement may target U.S. government facilities, U.S. private interests, and U.S. citizens,” the U.S. embassy warning reads.

“Potential targets include public events, such as demonstrations, holiday events, and celebratory gatherings; hotels, clubs, and restaurants popular with U.S. citizens; places of worship; schools; shopping malls and markets; tourism infrastructure; public transportation and airports,” the American embassy warning reads.

Stars and Stripes first reported the travel restriction, citing and administrative message distributed by EUCOM’s plans and operations center. The message warned of “potential unrest due to the United States’ change in policy toward settlements in the West Bank,” Stars and Stripes reported.

Secretary of State Mike Pompeo told reporters Monday that the U.S. would no longer view Israeli settlements in the West Bank as a violation of international law.

“Calling the establishment of civilian settlements inconsistent with international law hasn’t worked,” Pompeo told reporters. "It hasn’t advanced the cause of peace.

In 1978, President Jimmy Carter said the settlements in the West Bank were inconsistent with international law. The settlements have in the past been described by U.S. officials as illegitimate.

“The hard truth is there will never be a judicial resolution to the conflict,” Pompeo said. The conflict in between the Israelis and Palestinians is a complex political issue that can only be solved through negotiations between the two combative sides, Pompeo said.

It’s at least the second known instance of the U.S. military having to issue warnings to U.S. service members or tighten security following White House policy announcements regarding Israel.

In 2018, the 26th Marine Expeditionary Unit loitered in the Red Sea for a month prepared to provide security, evacuations or quick reaction forces in the event of violence stemming from the controversial move of the U.S. embassy to Jerusalem, according to a military command chronology obtained by Military Times through a government records request.

The Wasp-class amphibious assault ship Iwo Jima loitered in the North Red Sea for the entire month of May in 2018 after assuming an “elevated crisis response posture” in response to the U.S. embassy move from Tel Aviv to Jerusalem, a command chronology of the 26th MEU detailed.

During that May, the MEU said it was focused on “high risk embassies” in Amman, Beirut and Cairo, as the U.S. prepared to move the embassy to Jerusalem, according to the chronology.

The decision by President Donald Trump to move the American embassy to Jerusalem stoked international condemnation.