At least one Israeli strike hit Beirut's southern suburbs early on Wednesday morning, Reuters witnesses said, hours after the U.S. said it opposed the scope of Israeli attacks in Beirut amid a rising death toll and fears of wider regional escalation.

Reuters witnesses heard two blasts and saw plumes of smoke emerging from two separate neighbourhoods. It came after Israel issued an evacuation order early on Wednesday which mentioned only one building.

The Israeli military has in recent weeks carried out strikes on Beirut's southern suburbs, a Hezbollah stronghold, without advance warnings, or issued a warning for one area while striking more broadly.

The Israeli military said it conducted a strike on an underground Hezbollah weapons stockpile in the southern Beirut suburb of Dahiyeh.

"Prior to the strike, numerous steps were taken to mitigate the risk of harming civilians, including advancing warnings to the population in the area," the Israeli military said.

Israeli military evacuation orders were also affecting more than a quarter of Lebanon, according to the U.N. refugee agency, two weeks after Israel began incursions into the south of the country that it says are aimed at driving back Hezbollah.

Some Western countries have been pushing for a ceasefire between the two neighbours, as well as in Gaza, though the United States says it continues to support Israel and was sending an anti-missile system and troops.

On Tuesday, State Department spokesperson Matthew Miller said the U.S. had expressed its concerns to Prime Minister Benjamin Netanyahu's administration on the recent strikes.

"When it comes to the scope and nature of the bombing campaign that we saw in Beirut over the past few weeks, it's something that we made clear to the government of Israel we had concerns with and we were opposed to," he told reporters, adopting a harsher tone than Washington has taken so far.

The last time Beirut was hit was on Oct. 10, when two strikes near the city centre killed 22 people and brought down entire buildings in a densely populated neighbourhood.

Leaders and infrastructure targeted

The Middle East, meanwhile, has been on edge since Iran attacked Israel with a barrage of missiles on Oct. 1 after a similar large-scale operation in April. Israel has promised to retaliate.

Iran's allies in its "Axis of Resistance" to Israeli and U.S. interests - Lebanon's Hezbollah, Yemen's Houthis and armed groups in Iraq - have staged attacks in the region in support of Hamas in the Gaza war, complicating efforts to ease tensions.

Iranian Foreign Minister Abbas Araqchi is visiting Jordan, Egypt and Turkey as part of Tehran's diplomatic reach-out to countries of the region "to end genocide, atrocity and aggression", the Iranian foreign ministry's spokesperson said on Wednesday in a post on X.

Israel has been turning up the heat on Iran's most powerful regional ally Hezbollah since it began incursions into Lebanon after killing Hezbollah leaders and commanders, including its veteran secretary-general Hassan Nasrallah last month in the biggest blow to the group in decades.

On Tuesday, Netanyahu told President Emmanuel Macron of France during a phone conversation that he opposed a unilateral ceasefire and said he was "taken aback" by Macron's plan to hold a conference on Lebanon, according to an Israeli readout.

"A reminder to the French President: It was not a UN decision that established the State of Israel but the victory that was achieved in the War of Independence ... ," Netanyahu's office said in a separate statement.

The Elysee Palace did not immediately respond to a request for comment. The pair have previously clashed, including over Macron's call to halt arm sales to Israel.

With diplomatic efforts stalled, the fighting continues.

Israeli strikes in Lebanon have killed at least 2,350 people over the last year and left nearly 11,000 wounded, according to the health ministry, and more than 1.2 million people have been displaced.

The toll does not distinguish between civilians and combatants but includes hundreds of women and children.

The figures underscore the heavy price Lebanese are paying as Israel tries to destroy Hezbollah's infrastructure in their conflict, which resumed a year ago when it began firing rockets at Israel in support of Hamas at the start of the Gaza war.