Donald Trump isn't the first president to order military strikes without congressional approval. But his decision to bomb Iran comes at a uniquely volatile moment — both at home and abroad.

Overseas, the U.S. risks deeper entanglement in the Middle East if fighting erupts again between Israel and Iran. At home, Trump continues to sidestep oversight, showing little regard for checks and balances.

Iran said Tuesday it had begun efforts to rebuild residential areas and public infrastructure damaged in Israeli strikes over 12 days.

"We witnessed attacks on residential areas, as well as on scientific centres, research institutes, healthcare facilities and civilians... therefore we are facing a major task ahead in terms of reconstruction," government spokeswoman Fatemeh Mohajerani told state TV, adding that the authorities have begun to assess the extent of the damage.

U.S. President Donald Trump said Tuesday he would "probably" meet Ukrainian President Volodymyr Zelensky on the sidelines of a NATO summit in The Hague.

"Yeah probably I'll see him," Trump told reporters on Air Force One.

Russian drones, missiles and artillery killed at least 18 civilians and injured more than 100 others in Ukraine, officials said Tuesday, as Ukrainian President Volodymyr Zelenskyy sought guarantees of further Western military aid for his country's efforts to repel Russia's invasion.

Russian forces have relentlessly blasted civilian areas of Ukraine throughout the war, which is now in its fourth year. More than 12,000 Ukrainian civilians have been killed, according to the United Nations. Ukraine has also launched long-range drones against Russia, hitting residential areas.

Iran announced it had launched missiles at a major U.S. base in Qatar on Monday in retaliation for American strikes on key nuclear facilities, with explosions ringing out in Doha and projectiles seen streaking overhead.

U.S. President Donald Trump and his NATO counterparts are due to gather Tuesday for a summit that could unite the world's biggest security organization around a new defense spending pledge or widen divisions among the 32 allies.

Just a week ago, things had seemed rosy. NATO Secretary-General Mark Rutte was optimistic the European members and Canada would commit to invest at least as much of their economic growth on defense as the United States does for the first time.

Donald Trump thinks Iranians should overthrow their government if it refuses to negotiate on its nuclear program, but the US president is "still interested" in diplomacy, the White House said Monday.

"If the Iranian regime refuses to come to a peaceful diplomatic solution, which the president is still interested and engaging in, by the way, why shouldn't the Iranian people take away the power of this incredibly violent regime that has been suppressing them for decades?" Press Secretary Karoline Leavitt said on Fox News.

Several close U.S. allies urged a return to the negotiating table following American strikes on Iran that fueled fears of a wider conflict, while noting the threat posed by Tehran's nuclear program. Some countries and groups in the region, including those that support Iran, condemned the move while also urging de-escalation.

U.S. President Donald Trump described the damage as "monumental" after the U.S. hit three Iranian nuclear sites, though the U.S. assessment was unfinished.

Russian President Vladimir Putin on Monday slammed strikes on Tehran as "unprovoked aggression" and said Moscow was trying to help the Iranian people as he hosted Iranian Foreign Minister Abbas Araghchi in Moscow.

"This is an absolutely unprovoked aggression against Iran," Putin told Araghchi, calling the strikes "unjustified" and adding that Russia was "making efforts to provide assistance to the Iranian people."

Israeli strikes on Monday hit a power supply system in the Iranian capital, triggering outages in some areas around the city, Iranian media reported.

The power distribution line in northern Tehran "was damaged, causing outages in some areas", Fars news agency reported.