Iran's president said his country is fighting a "full-scale war" with the United States, as Washington expanded its strikes across the Islamic republic and Tehran hit Gulf states.

Here are the latest developments on Monday:

US forces launched a new round of strikes against Iran, US Central Command said.

The strikes, which began at 2000 GMT, are "designed to further degrade Iranian military capabilities used to attack commercial shipping in the Strait of Hormuz," CENTCOM said.

Sirens sounded in the Jordanian capital Amman, an AFP correspondent said. 

Jordan's army said that air defences had downed three Iranian missiles, with no injuries or damage reported.

Yemen's Iran-backed Houthi rebels announced a maritime embargo of Saudi Arabia, after the two adversaries traded fire last week for the first time in years.

The Houthis' naval blockade, if enforced, could further strain Saudi Arabia's economy by cutting off access to its Red Sea ports, which have been vital for oil exports redirected from the Strait of Hormuz.

Stephane Dujarric, the spokesman for the UN secretary-general, warned that the Houthi threat against Saudi Arabia "leads to the risk of an even wider regional escalation." 

Saudi Arabia condemned the Houthi announcement. A foreign ministry statement said Riyadh "continues to support the brotherly Yemeni people and their legitimate government."

Yemen's Iran-backed Houthi rebels announced a maritime embargo of Saudi Arabia, after the two adversaries traded fire last week for the first time in years.

The Houthis' naval blockade, if enforced, could further strain Saudi Arabia's economy by cutting off access to its Red Sea ports, which have been vital for oil exports redirected from the Strait of Hormuz.

Stephane Dujarric, the spokesman for the UN secretary-general, warned that the Houthi threat against Saudi Arabia "leads to the risk of an even wider regional escalation." 

Saudi Arabia condemned the Houthi announcement. A foreign ministry statement said Riyadh "continues to support the brotherly Yemeni people and their legitimate government."

The US State Department said operations had started in "pilot zones" in Froun, Srifa and Zawtar al-Gharbiya.

It is the first test on the ground of a deal to secure an Israeli withdrawal from south Lebanon and the disarmament of Hezbollah.

An Israeli military official said the Israel army will adjust its troop deployment in one of three zones Lebanese Armed Forces will exercise sole security control.

Iranian President Masoud Pezeshkian said his country was in a "full-scale war" with the United States and that Tehran should "accept the natural consequences of this resistance".

Oil prices closed higher, driven by continued hostilities between Washington and Tehran, despite some signs suggesting negotiations between the two countries. 

The price of Brent crude from the North Sea, for September delivery, rose to $89.22 a barrel. 

© Agence France-Presse