Israel and Iran traded strikes a week into their war on Friday as President Donald Trump weighed U.S. military involvement and key European ministers meeting with Iran’s top diplomat in Geneva scrambled to negotiate a diplomatic solution to the conflict.

To give diplomacy a chance, Trump said he would put off deciding for two weeks whether to join Israel’s air campaign against Iran. U.S. participation would most likely involve strikes against Iran’s underground Fordo uranium enrichment facility, considered to be out of reach to all but America’s “bunker-buster” bombs.

Whether or not the U.S. joins, Israeli Prime Minister Benjamin Netanyahu said Israel’s military operation in Iran would continue “for as long as it takes” to eliminate what he called the existential threat of a nuclear-armed Iran.

Before flying to Switzerland for talks, Iran’s top diplomat rejected nuclear negotiations with the U.S. while Israel continues to attack. Israel said its warplanes hit dozens of military targets in Iran early Friday, including missile-manufacturing facilities.

“It is the Americans who want talks,” Foreign Minister Abbas Araghchi said in comments broadcast Friday by Iranian state television. “They’ve sent messages several times – very serious ones – but we made it explicitly clear to them that as long as this aggression and invasion continue, there is absolutely no room for talk or diplomacy.”

Before the gathering, French President Emmanuel Macron said European diplomats would make “comprehensive, diplomatic and technical offer of negotiation” to Iran.

“We need to regain control on (Iran’s nuclear) program through technical expertise and negotiation,” he said.

Iran previously agreed to limit its uranium enrichment and allow international inspectors in to its nuclear sites under a 2015 deal with the U.S., France, China, Russia, Britain and Germany in exchange for sanctions relief. But after Trump pulled the U.S. unilaterally out of the deal during his first term, Iran began enriching uranium up to 60% – a short, technical step away from weapons-grade levels of 90% – and restricting access to its facilities.

Even with negotiations in Geneva underway, Iran kept up its strikes on Israel. Missiles crashed into the northern city of Haifa, sending plumes of smoke billowing over the Mediterranean port and wounding at least 19 people.

The war between Israel and Iran erupted June 13, with Israeli airstrikes targeting nuclear and military sites, top generals and nuclear scientists. At least 657 people, including 263 civilians, have been killed in Iran and more than 2,000 wounded, according to a Washington-based Iranian human rights group.

Iran has retaliated by firing 450 missiles and 1,000 drones at Israel, according to Israeli army estimates. Most have been shot down by Israel’s multitiered air defenses, but at least 24 people in Israel have been killed and hundreds wounded.

The risk of attacking nuclear reactors

Addressing an emergency meeting of the U.N. Security Council, the head of the International Atomic Energy Agency appealed for a halt to the fighting and warned against attacks on Iran’s nuclear reactors, particularly its only commercial nuclear power plant in the southern city of Bushehr.

“I want to make it absolutely and completely clear: In case of an attack on the Bushehr nuclear power plant, a direct hit would result in a very high release of radioactivity to the environment,” said Rafael Grossi, chief of the U.N. nuclear watchdog. “This is the nuclear site in Iran where the consequences could be most serious.”

Israel has not targeted Iran’s nuclear reactors, instead focusing its strikes on the country’s uranium enrichment sites – including the country’s main enrichment site at Natanz, centrifuge workshops around Tehran and a nuclear site in Isfahan.

Grossi also warned of the risks associated with attacking those nuclear sites, saying Israel’s attacks on Natanz caused some radiological and chemical contamination.

But the watchdog has reported that radiation levels outside the Natanz facility remain normal, as the risks of contamination are lower at enrichment sites.

“A diplomatic solution is within reach if the necessary political will is there,” Grossi said.

Iran has long maintained its nuclear program is for peaceful purposes. But it is the only non-nuclear-weapon state to enrich uranium up to 60%. Israel is widely believed to be the only Middle Eastern country with a nuclear weapons program but has never acknowledged it.

Israel hits Iran’s missile production

Dozens of Israeli warplanes struck targets across the country early Friday, including industrial sites in the north, missile storage and launchers in the west and the headquarters of an advanced research institute in Tehran.

The U.S in the past has linked that institute, known by its acronym SPND, to alleged Iranian research and testing tied to the possible development of nuclear explosive devices.

Iranian state media reported explosions as a result of Israeli strikes in an industrial area of Rasht, along the coast of the Caspian Sea in northern Iran, but did not acknowledge hits to the other sites. Iranian authorities have not discussed the damage done so far to the country’s military in the weeklong war.

“We are strengthening our air control in the region and advancing our air offensive,” Israeli military spokesperson Brig. Gen. Effie Defrin told reporters.

The military had warned the public to evacuate the area around Rasht’s Industrial City, southwest of the city’s downtown. But with Iran’s internet shut off to the outside world – now for more than 48 hours – it’s unclear just how many people could see the message.

Damage from Iranian missiles in Israel

As Araghchi landed in Geneva, new Iranian missile barrages set off air-raid sirens in Jerusalem and Tel Aviv. Explosions thundered and shrapnel was scattered in the southern city of Beersheba, a frequent target of missile strikes where a hospital suffered heavy damage on Thursday.

The Israeli military has destroyed what it assesses to be most of Iran’s ballistic missile launchers, contributing to the steady decline in Iranian attacks since the start of the conflict.

But several missiles slipped through Israel’s vaunted aerial defense system on Friday, with one projectile landing near the main port of Haifa. The strike wounded at least 19 people, according to the city’s Rambam Medical Center. It also caused damage to several buildings in the central district home to government offices.

From the ruins of the Weizmann Institute of Science hit in an Iranian missile barrage earlier this week, Netanyahu said Israel would fight as long as necessary to diminish Iran’s nuclear program and ballistic missile capacities.

“As long it takes because we face an existential danger, a dual existential danger,” he said, pointing to the destruction inflicted on one of Israel’s top research centers. “One from 20,000 such rockets … and the other of course from atomic bombs in the hands of this mad regime.”