The fragile ceasefire in the ongoing US-Iran conflict faced renewed challenges on Sunday, as a cargo ship caught fire after being struck by an unidentified projectile near Qatar’s coast, while Kuwait reported a drone attack, authorities said.

The incidents underscored the volatility of the month-old truce, which the Trump administration says is still in effect.

The ceasefire has been strained by Iran’s restrictions on traffic through the strategically vital Strait of Hormuz and the US blockade of Iranian ports.

Washington is awaiting Tehran’s response to a proposed deal aimed at ending the conflict, reopening the strait for shipping, and rolling back Iran’s nuclear programme.

A key point of contention remains Iran’s stockpile of highly enriched uranium, which the UN nuclear watchdog says exceeds 440 kilograms at up to 60% purity — a short step from weapons-grade material.

Iran’s military has stressed that it is on “full readiness” to protect sites storing the uranium.

Brig-Gen. Akrami Nia told Iranian state media that authorities were prepared for potential infiltration or airborne threats against the nuclear facilities, without providing additional details.

Sunday’s naval incident occurred 23 nautical miles northeast of Doha, the United Kingdom Maritime Trade Operations Centre (UKMTO) reported.

The attack sparked a small fire aboard the vessel, which was quickly extinguished, and no casualties were reported.

The ship’s ownership and origin were not disclosed, and no group has claimed responsibility.

Meanwhile, Kuwaiti authorities said that hostile drones entered the country’s airspace early Sunday, prompting a defensive response.

There were no immediate reports of injuries or damage.

US President Donald Trump has repeated warnings that full-scale military action could resume if Iran does not agree to reopen the strait and roll back its nuclear activities.