WASHINGTON — President Donald Trump said any decision on potential US involvement would be made within two weeks as the Iran-Israel air war entered its second week on Friday.

Israeli air attacks have killed 639 people in Iran, said the Human Rights Activists News Agency. Those killed include the military's top echelon and nuclear scientists. Israel has said at least two dozen Israeli civilians have died in Iranian missile attacks. The death toll from either side could not be independently verified.

Israel has targeted nuclear sites and missile capabilities, but also has sought to shatter the government of Supreme Leader Ayatollah Ali Khamenei, according to Western and regional officials.

"Are we targeting the downfall of the regime? That may be a result, but it's up to the Iranian people to rise for their freedom," Israeli Prime Minister Benjamin Netanyahu said on Thursday.

Iran has said it is targeting military and defense-related sites in Israel, but it has also hit a hospital and other civilian sites.

Israel accused Iran on Thursday of deliberately targeting civilians through the use of cluster munitions, which disperse small bombs over a wide area. Iran’s mission to the United Nations did not immediately respond to a request for comment.

With neither country backing down, the foreign ministers of Britain, France and Germany along with the European Union foreign policy chief were due to meet in Geneva with Iran's foreign minister to try to de-escalate the conflict on Friday.

"Now is the time to put a stop to the grave scenes in the Middle East and prevent a regional escalation that would benefit no one," said British Foreign Minister David Lammy ahead of their joint meeting with Abbas Araqchi, Iran's foreign minister.

Russian President Vladimir Putin and Chinese President Xi Jinping both condemned Israel and agreed that de-escalation is needed, the Kremlin said on Thursday.

Russia, on Thursday, warned the United States against 'military intervention' in Iran-Israel war, according to AFP.

"We would like to particularly warn Washington against military intervention in the situation, which would be an extremely dangerous step with truly unpredictable negative consequences," Russia's foreign ministry's spokeswoman Maria Zakharova told reporters.

The head of Russia's nuclear energy corporation warned on Thursday that an Israeli attack on Iran's Bushehr nuclear power plant could lead to a "Chernobyl-style catastrophe".

An Israeli military spokesperson said Israel had struck the site, but an Israeli military official later called this statement "a mistake" and said he could neither confirm nor deny that the Bushehr site on the cost of the Gulf had been hit.

Bushehr is Iran's only operating nuclear power plant and was built by Russia, per Reuters.

The role of the United States, meanwhile, remained uncertain. On Thursday in Washington, Lammy met with US Secretary of State Marco Rubio and Trump's special envoy to the region, Steve Witkoff, and said they discussed a possible deal.

Witkoff has spoken with Araqchi several times since last week, sources say. Trump, meanwhile, has alternated between threatening Tehran and urging it to resume nuclear talks that were suspended over the conflict.

Trump has mused about striking Iran, possibly with a "bunker buster" bomb that could destroy nuclear sites built deep underground. The White House said on Thursday Trump would decide in the next two weeks whether to get involved in the war.

Trump often invokes a two-week time period when faced with a difficult situation. The president told senior aides late Tuesday that he approved of attack plans for Iran, but was waiting to see if Tehran would abandon its nuclear program, people familiar with the deliberations said.

A day earlier, Trump announced that he was considering joining Israel on the strikes against Iran. "I may do it, I may not do it," he said.

On Wednesday, Russia's Deputy Foreign Minister Sergei Ryabkov warned the US against offering direct military aid to Israel. Ryabkov said, "We caution Washington against even speculative, hypothetical options of this kind. It would be a step that would radically destabilize the entire situation."

With the Islamic Republic facing one of its greatest external threats since the 1979 revolution, any direct challenge to its 46-year-long rule would likely require some form of popular uprising.

But activists involved in previous bouts of protest say they are unwilling to unleash mass unrest, even against a system they hate, with their nation under attack.

"How are people supposed to pour into the streets? In such horrifying circumstances, people are solely focused on saving themselves, their families, their compatriots, and even their pets," said Atena Daemi, a prominent activist who spent six years in prison before leaving Iran.

Meanwhile, as the conflict enters its second week, Israel and Iran continue to exchange fire. An Israeli hospital was hit by an Iranian missile. Israel says it struck 100 targets in Iran, including the heavy-water reactor in Arak and a site at Natanz it says was being used for nuclear-weapons development. — Agencies