Beirut (Lebanon) (AFP) - Lebanon declared a national day of mourning on Thursday after Israeli strikes pummelled the country, killing nearly 200 people and calling into question the ceasefire between the United States and Iran.

Washington and Tehran had both claimed victory in the Middle East war after agreeing a two-week truce and negotiations aimed at ending a conflict that has killed thousands across the region and plunged the global economy into turmoil.

But fractures emerged quickly, especially when Israel carried out its heaviest strikes yet on neighbouring Lebanon since the Iran-backed militant group Hezbollah joined the war in early March.

At least 182 people were killed and nearly 900 wounded on Wednesday, the Lebanese health ministry said.

There had been conflicting messages about whether the fighting in Lebanon was included in the truce, with Israel insisting that it was not.

The Lebanese prime minister’s office said Thursday would be “a national day of mourning for the martyrs and wounded of the Israeli attacks that targeted hundreds of innocent, defenceless civilians”, ordering the closure of public administrations and the lowering of flags.

Hours later, Hezbollah said it had fired rockets towards Israel in response to what it called a violation of the US-Iran truce.

US Vice President JD Vance backed Israel in saying Lebanon was excluded from the truce, days before he was due to lead talks with Tehran in Pakistan.

“If Iran wants to let this negotiation fall apart… over Lebanon, which has nothing to do with them, and which the United States never once said was part of the ceasefire, that’s ultimately their choice,” he said.

- ‘Running left and right’ -

But Iran’s speaker of parliament Mohammad Bagher Ghalibaf appeared to threaten the ceasefire, posting on X that the “workable basis on which to negotiate” had already been violated, making further talks “unreasonable”.

Ghalibaf listed three alleged US violations of the truce plan: the continued attacks in Lebanon, a drone entering Iranian airspace and Washington’s opposition to the country’s right to uranium enrichment.

Adding to the fragility of the truce, a senior US official said Iran’s 10-point plan was not the same set of conditions the White House had agreed to in order to pause the war.

In Lebanon, where UN rights chief Volker Turk called the scale of killing “horrific”, strikes across the capital Beirut that came without warning triggered horror and panic.

“People started running left and right, and smoke was billowing,” said Ali Younes, who was waiting for his wife near Corniche Al-Mazraa, one of the areas targeted.

More than 1,700 people have been killed in Lebanon since Israel launched airstrikes and a ground invasion last month, local officials said.

Iran’s Revolutionary Guards warned they would “fulfil our duty and deliver a response” if Israel did not cease its strikes, while Hezbollah said it had a right to respond.

Israeli Prime Minister Benjamin Netanyahu said the country remained prepared to confront Iran if necessary, while Trump said US forces would remain deployed to the region until a “real agreement” was reached and complied with.

- High-stakes talks -

The bellicose rhetoric came ahead of high-stakes talks in Pakistan expected on Friday or Saturday.

Iran’s ambassador to Pakistan announced that the country’s delegation would arrive in Islamabad on Thursday for “serious talks” on the terms of a peace deal.

A key point of contention remains the Strait of Hormuz, through which a fifth of the world’s oil as well as vast quantities of natural gas and fertiliser pass in peacetime.

Iran announced alternative routes on Thursday for ships travelling through the strait,

But it was unclear if Tehran was allowing vessels to pass through the strait, following reports on Wednesday suggesting it was shut – something the White House called “completely unacceptable”.

- ‘More relaxed’ -

Pakistani Prime Minister Shehbaz Sharif, whose country mediated the ceasefire, called in a social media post for all parties to “exercise restraint and respect the ceasefire for two weeks” to allow diplomacy to take hold.

Further casting doubt on the truce’s durability, Iranian state media announced fresh missile and drone attacks against US-allied Gulf states in retaliation for airstrikes on its oil facilities, with Kuwait, the UAE, Saudi Arabia and Bahrain all reporting strikes since the ceasefire took effect.

In Tehran, streets were quieter than usual on Wednesday, with many shops closed after a long and anxious night for residents fearing a massive US attack.

“Everyone is at ease now,” said Sakineh Mohammadi, a 50-year-old housewife, adding she was “proud” of her country.

“We are more relaxed.”