(TNS) — The U.S. State Department issued a worldwide travel advisory earlier this week urging Americans to use caution when traveling abroad.

The “Worldwide Caution” alert, issued on Sunday, came one day after the U.S. attacked nuclear sites in Iran.

“The conflict between Israel and Iran has resulted in disruptions to travel and periodic closure of airspace across the Middle East,” the advisory said. “There is the potential for demonstrations against U.S. citizens and interests abroad. The Department of State advises U.S. citizens worldwide to exercise increased caution.”

The State Department then encourages U.S. citizens to check the travel advisory page for updates on any country they plan on visiting.

The department issues four levels of advisories for other countries, the highest being “Level 4 — Do Not Travel.” Current countries that fall under this advisory include Iran, Israel, Ukraine, Russia, Haiti and Venezuela.

The Department of Homeland Security issued a similar alert on Sunday, warning that “the ongoing Iran conflict is causing a heightened threat environment in the United States. Low-level cyber attacks against US networks by pro-Iranian hacktivists are likely, and cyber actors affiliated with the Iranian government may conduct attacks against US networks.”

“Iran also has a long-standing commitment to target US Government officials it views as responsible for the death of an Iranian military commander killed in January 2020,” the alert says. “The likelihood of violent extremists in the Homeland independently mobilizing to violence in response to the conflict would likely increase if Iranian leadership issued a religious ruling calling for retaliatory violence against targets in the Homeland. Multiple recent Homeland terrorist attacks have been motivated by anti-Semitic or anti-Israel sentiment, and the ongoing Israel-Iran conflict could contribute to US-based individuals plotting additional attacks.”

That alert is not set to expire until Sept. 22.