Iran has stepped up its missile campaign against Israel and is refusing to discuss a ceasefire unless it receives firm guarantees against further attacks.

Reporting from Tehran, Mohamed Vall said the Islamic Revolutionary Guard Corps had intensified its response, launching what it described as the 33rd wave of Operation Promise 4.

The IRGC said future attacks would involve only its heaviest missiles, including projectiles weighing more than one tonne, in a sign of Tehran’s hardening military stance.

Iran’s deputy foreign minister said China, France and Russia had made contact over the possibility of a ceasefire, but gave no indication that any breakthrough was close.

He made clear Tehran would not return to negotiations unless it was assured that attacks such as the current assault, and those seen in June, would not be repeated — a position that suggests Iran remains far from rejoining diplomatic talks.