An Iranian ship purportedly carrying aid to Yemen should change course and head to Djibouti where the United Nations is overseeing humanitarian deliveries, U.S. officials demanded Tuesday.

The U.S. military is tracking the ship after Tehran reportedly said it would send warships to escort the vessel to Yemen, Pentagon spokesman Colonel Steven Warren told reporters.

Iraq's President Fuad Masum arrived on Tuesday in Tehran for a two-day visit expected to focus on the fight against the Islamic State group and also on economic ties.

Masum arrived with the Baghdad government's ministers for trade, tourism and the environment, state media said. and they were welcomed at Mehrabad Airport by Mohammad Reza Nematzadeh, Iran's minister for trade, industry and mines.

Iranian nuclear negotiator Abbas Araghchi said on Tuesday he was "very hopeful" that an accord on Tehran's nuclear program could be reached with world powers ahead of the June 30 deadline.

"Different elements inside and outside of the negotiation chamber can prevent a deal but despite all of this, we will continue the negotiations and we are very hopeful that we can reach a deal before the deadline," he said at the start of a new round of talks in Vienna.

The U.S. Senate overwhelmingly passed a resolution Monday calling for Iran to release three American citizens being held in the country.

The non-binding measure, which passed 90 votes to zero, urges the White House to use all tools available to seek and obtain the return of the detained Americans, who include pastor Saeed Abedini, Washington Post journalist Jason Rezaian and former U.S. Marine Amir Hekmati.

Undersecretary of State Wendy Sherman will lead a U.S. delegation to Vienna May 13 to join the next round of negotiations on finalizing an Iran nuclear accord, the State Department said Monday.

The American team, which includes a representative of President Barack Obama's National Security Council and experts on arms control, non-proliferation, economic sanctions and energy, departs Wednesday. 

Saudi Arabia's new foreign minister insisted Monday that King Salman's last minute decision not to attend a Camp David summit was not intended as a snub to the United States.

"This is not related in any way, shape or form to any disagreement between the two countries," Foreign Minister Adel al-Jubeir told reporters at Saudi Arabia's embassy Washington.

Turkish Prime Minister Ahmet Davutoglu has rejected claims that Ankara is preparing to intervene militarily in neighboring Syria, local media reported on Saturday.

"No, there is no situation right now that requires Turkey's involvement," Davutoglu was quoted as saying by the Hurriyet newspaper. 

A top adviser to the Iranian president called on Saturday for a more active British foreign policy in the Middle East after Prime Minister David Cameron's upset election victory.

The remarks by Hamid Aboutalebi, President Hassan Rouhani's deputy chief of staff for political affairs, come as six major powers, including Britain, seek a nuclear deal with the Islamic republic.

Russian Ambassador to Lebanon Alexander Zasypkin defended on Saturday Hizbullah's intervention in Syria, describing the group as a resistance that participates in political life and aids a legitimate regime in Syria.

The ambassador rejected in comments published in the pan-Arab daily al-Hayat comparison between the Islamic State of Iraq and the Levant (ISIL) and Hizbullah, stressing that the differences are “fundamental.”

U.S. Secretary of State John Kerry met Gulf foreign ministers in Paris on Friday ahead of a summit in which President Barack Obama will seek to reassure the Arab monarchies over his Iran policy.

Fresh from a trip to Riyadh where he urged a ceasefire in Yemen, Kerry met foreign ministers from the six members of the Gulf Cooperation Council: Qatar, Kuwait, Bahrain, Oman, the United Arab Emirates and Saudi Arabia.