India, June 30 -- Iran said it is not convinced and has "serious doubts" that a tentative US-brokered ceasefire with Israel will hold, signaling it is ready to strike back if hostilities resume.

"We have serious doubts about the enemy's commitment to its obligations, including the ceasefire," the semi-official Fars News Agency quoted Iran's armed forces chief of staff, Abdolrahim Mousavi, as saying.

"We are prepared to deliver a firm response if aggression is repeated," Abdolrahim Mousavi added.

Mousavi made the comments in a Sunday phone call with Saudi Defense Minister Khalid bin Salman, addressing the fragile truce that began on Tuesday, June 24.

The Iran-Israel conflict began on June 13 with Israeli strike that killed several seni...