Israeli officials said they are closely monitoring Iran's efforts to rebuild missile production sites destroyed by Israeli strikes in June and will act if new threats emerge.

Satellite images taken by Planet Labs showed that Iran is rebuilding facilities previously targeted by Israel, Sam Lair, a research associate at the James Martin Center for Nonproliferation Studies who reviewed the imagery, told The Wall Street Journal.

Prime Minister Benjamin Netanyahu, speaking Wednesday at a graduation ceremony for Israeli Air Force pilots, said Israel was watching Iran and its terrorist proxies, Hamas and Hezbollah, as they rearm and would respond if necessary, according to the Journal.

Defense Minister Israel Katz, speaking at the same event, said Israel would move to prevent emerging threats.

"We are not looking for confrontations, but our eyes are open to any possible danger," Netanyahu said.

Netanyahu is preparing to travel to the United States for a year-end meeting with President Donald Trump. Israel's assessment of Iran's ballistic missile activity and potential next steps are expected to be discussed during the visit, an Israeli official told the Journal.

U.S. officials, however, have expressed concern privately about Israel's willingness to use force, according to the Journal.

Trump has warned Iran against rebuilding its nuclear facilities but has not publicly addressed missile production.

"As President Trump has said, if Iran pursued a nuclear weapon, that site would be attacked and would be wiped out before they even got close," White House spokeswoman Anna Kelly told the Journal when asked whether the administration would support an Israeli strike tied to Iran's missile program.

Any Israeli attack would likely require at least tacit U.S. approval, as Israel would need American assistance to defend against retaliatory missile strikes from Iran.

Israel has warned Iran that efforts to rebuild its nuclear or missile capabilities would trigger further action. Analysts said Iran is moving to restore missile manufacturing while proceeding more cautiously with its nuclear facilities.

Earlier this month, a U.S. special operations team seized military-related goods bound for Iran from China during a boarding operation in the Indian Ocean, the Journal reported.

The Treasury Department also sanctioned 32 individuals and entities across Europe, the Middle East and Asia for supporting Iran's ballistic missile and drone programs.

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