Iran said on Wednesday its aid ship bound for war-torn Yemen is to dock in Djibouti for inspection, heading off a potential confrontation with the United States.

The aid "will be inspected in Djibouti. The ship will dock in Djibouti and the protocol laid down by the United Nations will be implemented," Deputy Foreign Minister Hossein Amir-Abdollahian said, quoted by the ISNA news agency.

The Afghan Taliban said Wednesday that a delegation from its Qatar-based political office had visited Iran for talks, as Kabul has made repeated overtures to the insurgent group to reopen peace negotiations.

In a statement announcing the visit, the Taliban's spokesman Zabiullah Mujahid presented the talks as if they were a meeting between two governments, rather than that of a militant group and a neighbor.

Iran's supreme leader Ayatollah Ali Khamenei on Wednesday ruled out allowing nuclear inspectors to visit military sites or to question scientists if Tehran strikes a long-sought deal with world powers.

"We have already said that we will not allow any inspections of military sites by foreigners," the official IRNA news agency quoted him as saying.

A delegation from the Afghan Taliban's Qatar-based political office is in Tehran for talks, Iranian media reported Tuesday.

The visitors, headed by Tayyab Agha, head of the political bureau, met Iranian security officials and discussed regional issues, "particularly developments in the Islamic world," Tasnim news agency said.

Syria's President Bashar Assad on Tuesday praised Iran's support as a "key pillar" in his fight against rebels, as a third Iranian official visited Damascus in less than a week.

The visits come after several military losses for the Syrian government and as Tehran negotiates a key nuclear deal with the United States, which backs the rebels fighting Assad.

The Washington Post's Tehran correspondent Jason Rezaian, in custody for 10 months, will appear in court next week accused of spying and other crimes against Iran, his lawyer said Tuesday.

Rezaian's wife, Yeganeh Salehi, an Iranian who is also a journalist, and another suspect -- both of whom are currently on bail -- have also been summoned to the court in the capital on May 26.

U.S. Secretary of State John Kerry took a risky gamble facing derision and much skepticism when he flew to Russia last week for the first time in two years to meet President Vladimir Putin.

But his bet may be beginning to pay off, as two top American diplomats were welcomed in Moscow on Monday for top-level talks for the first time in months on two crises bedeviling global affairs -- Ukraine and Syria.

Singapore on Monday condemned Iranian forces for firing warning shots in the Gulf at a commercial ship registered in the Asian city-state, calling it a "serious violation of international law".

The Maritime and Port Authority (MPA) also urged Tehran to investigate Thursday's incident involving the Singapore-flagged Alpine Eternity which it said was in international waters.

Israeli Prime Minister Benjamin Netanyahu said on Sunday there was still time to stop an Iranian agreement with world powers that he says would give Tehran nuclear arms.

"It's still not too late to retract the plan that gives Iran an agreement which will pave it a road to a nuclear weapon," he said at a ceremony marking Israel's capture of Arab east Jerusalem in the 1967 Six Day War.

An Iranian aid ship bound for Yemen in defiance of U.S. warnings has entered the Gulf of Aden and is expected to reach port on Thursday, media reported.

The vessel, the Iran Shahed, is carrying 2,500 tonnes of aid including flour, rice, canned food, medical supplies and bottled water, all urgently needed in the conflict-wracked and impoverished state.