Watch: Trump says US not seeking regime change in Iran as it brings 'chaos'

Israel believes Iran maintains undisclosed nuclear facilities that remain active, but it lacks intelligence on their locations, the Jewish State's Channel 14 reported Tuesday.

The report also referenced US intelligence estimates, which it said similarly suggest the existence of secret Iranian nuclear facilities that have not been targeted.

US President Donald Trump's statement that "China can now continue to purchase oil from Iran" merely acknowledged that oil from the Strait of Hormuz won't be disrupted, and was not a signal of sanctions relief, the Wall Street Journal reported citing a senior White House official.

“The President was simply calling attention to the fact that, because of his decisive actions to obliterate Iran’s nuclear facilities and broker a ceasefire between Israel and Iran, the Strait of Hormuz will not be impacted, which would have been devastating for China," the official was quoted as saying.

"The President continues to call on China and all countries to import our state-of-the-art oil rather than import Iranian oil in violation of US sanctions.”

Iranian air defense systems have been activated in several cities including Tabriz, Shahr-e Rey in southern Tehran, and Mashhad, according to local media reports.

However, officials have not confirmed any new Israeli attack.

"No attack has occurred. The air defense is countering micro aerial vehicles and securing the airspace,” Tabnak reported citing the Islamic Revolutionary Guards Corps in East Azerbaijan province.

Britain's ambassador to the UN Barbara Woodward in a meeting of the Security Council urged Iran "to take this opportunity to engage in negotiations now."

"It is critical that Iran does not miss this window for diplomacy," she added during the meeting held to discuss the stalled Iran nuclear talks.