Iran's President Hassan Rouhani has said Saudi Arabia's decision to cut diplomatic ties with Tehran "cannot cover its crime" of executing prominent Shia religious leader Nimr al-Nimr.
Riyadh on Sunday severed relations with Iran after its embassy in Tehran was set ablaze during protests against Saudi Arabia's execution of Nimr, who was put to death along with 46 other mostly Sunni convicts on terrorism charges.
"The Saudi government has taken a strange action and cut off its diplomatic relations with the Islamic Republic of Iran to cover its crimes," Rouhani said on Tuesday in a meeting with Danish Foreign Minister Kristian Jensen, reported by Iran's official IRNA news agency.
"Undoubtedly, such actions can't cover up that big crime," he added.
Rouhani's comments are the latest in an escalating diplomatic row between regional heavyweights Iran and Saudi Arabia that has raised international concerns over peace efforts to end the wars in Syria and Yemen - the nations support opposite sides in the two conflicts.
The Saudi ambassador to the UN said on Monday, though, that the severing of the ties "should have no effect" on attempts to end the wars.
"We will continue to work very hard towards supporting the peace efforts in Syria, in Yemen, wherever there might be a need for that," Abdullah al-Mouallimi told reporters in New York.
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"How is that going to affect the behaviour of Iran, we do not know, you will need to ask the Iranians for that," added al-Mouallimi, accusing Tehran of not being supportive of attempts to find peace before this latest falling out between the two nations.
"They have been taking provocative and negative positions and lines, and as such I don't think that the breaking of relations is going to dissuade them from such behaviour."
Earlier on Tuesday, Kuwait became the latest country in the region to back Riyadh, recalling its ambassador to Iran over the attacks on the Saudi diplomatic mission.
Bahrain, Sudan and the UAE have also rallied to Saudi Arabia's side, breaking off or downgrading relations with Iran in recent days.
Iran has accused Saudi Arabia of using the attack on the embassy as a pretext to fuel tensions.
Calls for restraint
On Sunday, UN Secretary-General Ban Ki-moon issued a statement criticising both the executions and the attack on the Saudi embassy in Tehran.
The US government also expressed public fears over the escalating war of words.
"We do continue to be concerned about the need for both the Iranians and the Saudis to de-escalate the situation," said White House spokesman Josh Earnest.
"We are urging all sides to show some restraint and to not further inflame tensions that are on quite vivid display in the region."
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Turkey said that it hoped the tension would diminish "as soon as possible".
"The region is already engulfed by a circle of fire, it can no longer bear bigger crises," said Numan Kurtulmus, Turkey's deputy prime minister.
"As a country which has friendly relations with Iran and Saudi Arabia, we believe that both countries should show restraint."
Source: Al Jazeera and agencies