A barrage of Iranian strikes caused havoc across the Gulf on Saturday, shattering the aura of peace so highly prized by the oil-rich region's wealthy rulers.

Missiles streaked across clear desert skies as smoke plumed from US bases in Manama and Abu Dhabi and loud thuds shook high-rise windows in Dubai.

In Qatar, dozens of people fled in panic as a falling missile plunged into a residential neighbourhood, erupting in a fireball as it hit the street.

By Phil Stewart and Idrees Ali

WASHINGTON, Feb 28 (Reuters) - Ahead of the U.S. attack on Iran, President Donald Trump received briefings that not only delivered blunt assessments about the risk of major U.S. casualties but also touted the prospect of a generational shift in the Middle East in favor of U.S. interests, a U.S. official told Reuters.

Feb 28 (Reuters) - Iran's Supreme Leader Ayatollah Ali Khamenei will speak within minutes, Iran's Al-Alam TV reported, hours after U.S., Israeli strikes targeted top Iranian leaders on Saturday.

(Reporting by Jaidaa Taha and Jana Choukeir, Editing by Nayera Abdallah)

KYIV, Feb 28 (Reuters) - Ukrainian President Volodymyr Zelenskiy said on Saturday that the time and place of the next round of peace talks between the U.S., Russia and Ukraine would depend on the security situation in the Middle East and the level of "real diplomatic possibilities".

Zelenskiy said he would issue fresh directives to Ukraine's negotiating team at the talks, without detailing what they were.

On Thursday, he had said the next round of talks would probably take place in Abu Dhabi in early March.

For weeks, Iranians had been nervously anticipating another attack by the United States and Israel, despite Tehran and Washington holding negotiations aimed at averting a violent showdown.

Nevertheless, on Saturday morning just before the strikes, life in Tehran was moving at its usual pace, taxis and buses were inching through mid-morning traffic and people were running errands.

Then the routine was shattered by a series of detonations. Security forces flooded the streets and dark columns of smoke rose near the home of Iran's supreme leader, Ayatollah Ali Khamenei.

Across Israel, city streets stood deserted on Saturday as residents took cover in shelters, while the blasts from Iranian missiles being intercepted reverberated overhead.

It was the second time in under a year that Israelis were undertaking this grim wartime routine, having first fled Iranian missiles during a 12-day war between the arch-foes last June.

The United States and Israel launched a wave of strikes against military targets in Iran on Saturday, sparking a rapid Iranian retaliation towards Israel.

The United States and Israel on Saturday defended their attacks on Iran, which called resulting civilian deaths a "war crime" during an emergency meeting of the UN Security Council.

"The international community has long affirmed a simple and necessary principle: Iran cannot have a nuclear weapon," said US ambassador Mike Waltz, pointing to past UN resolutions ignored by Tehran.

"That principle is not a matter of politics, it's a matter of global security, and to that end, the United States is taking lawful actions," he added.

KYIV, Feb 28 (Reuters) - Ukrainian President Volodymyr Zelenskiy, addressing U.S. strikes in Iran on Saturday, said it was important that Washington act decisively, but also that hostilities did not escalate into a wider war.

"Whenever there is American resolve, global criminals weaken," Zelenskiy, who has previously called for the Iranian government to be overthrown, wrote on social media.

"This understanding must also come to the Russians," he added.

Feb 28 (Reuters) - Israel and the United States launched strikes on Iran on Saturday, plunging the Middle East into a renewed military confrontation.

Tehran responded by launching missiles at Israel and called the strikes against it unprovoked and illegal.

Below is international reaction to the attacks:

GERMANY, FRANCE AND BRITAIN

In a joint statement, the three countries condemned Iranian attacks, saying Iran must refrain from indiscriminate military strikes.

BERLIN, Feb 28 (Reuters) - Germany, France and Britain condemned Iranian attacks on countries in the region on Saturday, saying Iran must refrain from indiscriminate military strikes and resume negotiations.

"We condemn Iranian attacks on countries in the region in the strongest terms," French President Emmanuel Macron, German Chancellor Friedrich Merz and British Prime Minister Keir Starmer said in a joint statement.