Tehran on Sunday dismissed its renewed blacklisting by Washington as a state sponsor of terrorism charging that it was U.S. allies including Riyadh that were the real culprits.

The Iranian foreign ministry noted its role in neighboring Iraq supporting the government against the Islamic State jihadist group independently of a U.S.-led coalition as well as its backing for the Syrian regime against jihadists and other rebels, some of them backed by Saudi Arabia.

Saudi Arabia's surprisingly high-profile injection of $3.5 billion into Uber signals a more aggressive global investment presence by a kingdom trying to wean its economy off oil.

Saudi authorities put to death a Nigerian on Sunday after convicting him of murdering a policeman, the latest in a surge of executions that has drawn concern from human rights groups.

It was 95th execution of the year in the ultra-conservative Muslim kingdom, which imposes the death penalty for offenses including murder, drug trafficking, armed robbery, rape and apostasy.

Iran said Sunday its pilgrims will miss this year's hajj because Saudi Arabia, custodian of Islam's holiest sites, was raising obstacles and "blocking the path to Allah" for its faithful.

Riyadh said Iran's hajj demands were "unacceptable."

Amnesty International warned on Friday that a surge in executions carried out by Saudi authorities could see more than 100 people put to death in the first six months of 2016.

The London-based watchdog says that the kingdom carried out at least 158 death sentences last year, making it the third most prolific executioner after Iran and Pakistan.

An Iranian delegation was traveling to Saudi Arabia on Tuesday for talks on the annual hajj pilgrimage despite a diplomatic crisis between the Gulf rivals, the official IRNA news agency reported.

"A delegation of six people will leave this afternoon for Saudi Arabia at the invitation of the Saudi Minister of Hajj for negotiations," it reported Said Ohadi, head of Iran's Hajj Organization, as saying.

Saudi Arabia put to death a citizen convicted of murder on Tuesday, bringing to 94 the number of executions in the kingdom this year.

Imad al-Assimi was found guilty of shooting dead a compatriot in a dispute, the interior ministry said in a statement carried by state news agency SPA.

A senior Saudi religious leader on Friday warned against those who would "wreak havoc" under the guise of pilgrimage, an apparent swipe at the kingdom's rival Iran.

The comments by Sheikh Saleh bin Abdullah bin Hameed at the Grand Mosque in Mecca coincide with a dispute between Shiite Iran and its Sunni regional rival Saudi Arabia over this year's hajj.

Saudi Arabia on Tuesday put to death a Pakistani man convicted of drug smuggling, bringing to 93 the number of executions in the kingdom this year.

Mohammed Ishaq Thawab Gul had been found guilty of trafficking heroin into the kingdom, the interior ministry said.

U.S. Secretary of State John Kerry held talks in Saudi Arabia on Sunday to secure its support ahead of a potential showdown with Russia at talks on the Syrian conflict.

After his Saudi meetings, Kerry was due to fly to Vienna which this week will host the international contact groups engaged in efforts to halt fighting in Syria and Libya.