Foreign Minister Julie Bishop says the Australian government is deeply disturbed by Saudi Arabia's mass execution of 47 people.
Ms Bishop also condemned protest attacks on the Saudi embassy in Tehran, after demonstrators stormed and set fire to it following the executions.
Most of the 47 men killed in what was Saudi Arabia's largest execution in three and a half decades were Sunnis, convicted of al Qaeda attacks in the kingdom a decade ago.
But it was the execution of prominent Shi'ite cleric Sheikh Nimr al-Nimr that has inflamed relations with Iran.
Saudi Arabia has announced it is severing diplomatic relations with Iran, calling home its diplomatic personnel and giving Iranian diplomatic personnel 48 hours to leave.
Ms Bishop has called on Iranian authorities to ensure proper protection of diplomatic facilities.
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"We call on all parties to look for ways to calm the recent tension and to exercise restraint in their actions and comments," she said on Monday.
"The Australian government supports the universal abolition of the death penalty and we are deeply disturbed by the recent executions carried out in Saudi Arabia."
But Ben Rich, researcher of Saudi politics at the University of New England, said Australia would likely keep turning a blind eye to Saudi Arabia's human rights record.
He said human rights "play a very, very distant second fiddle" to resources when it comes to the oil-rich Middle East nation.
"We, for a very long time, ignored the human rights violations by Saudi Arabia and I suspect we will continue to do that," he said.
Opposition defence spokesman Stephen Conroy said it was disappointing to see states inflaming tensions in the Middle East as the world tries to combat terrorism in the region.
"It is something that is a worry," he told Sky News.
"Governments should be taking a deep breath before they engage in what can be considered provocative actions."
Diplomatic ties severed
Saudi Arabia says it has severed ties with Iran over the storming of the Saudi embassy in Tehran.
It comes amid a worsening diplomatic crisis between the regional rivals following the kingdom's execution of a prominent Shi'ite cleric.
Foreign Minister Adel al-Jubeir told a news conference Iran's diplomatic mission and related entities in Saudi Arabia had been given 48 hours to leave.
He said Riyadh would not allow the Islamic Republic to undermine the Sunni kingdom's security.
'Message of blood'
Iranian protesters stormed the Saudi embassy in Tehran and Shi'ite Muslim Iran's top leader predicted 'divine vengeance' for Saudi Arabia's execution of a prominent Shi'ite cleric.
Strong rhetoric from Tehran was matched by Iran's Shi'ite allies across the region, with Sayyed Hassan Nasrallah, the head of Lebanese militia Hezbollah, describing the execution as "a message of blood". Moqtada al-Sadr, an Iraqi Shi'ite cleric, called for angry protests.
Tensions between revolutionary, mainly Shi'ite Iran and Saudi Arabia's conservative Sunni monarchy had already run high for years as they backed opposing forces in wars and political conflicts across the Middle East, usually along sectarian lines.
However, Saturday's execution of a cleric whose death Iran had warned would "cost Saudi Arabia dearly", and the storming of the kingdom's Tehran embassy, raised the pitch of that rivalry.
Demonstrators protesting against the execution of Sheikh Nimr al-Nimr broke into the embassy building, smashed furniture and started fires before being ejected by police.
Iran's President Hassan Rouhani condemned the execution as "inhuman", but also urged the prosecution of "extremist individuals" for attacking the embassy and the Saudi consulate in the northeastern city of Mashhad, state media reported.
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Tehran's police chief said an unspecified number of "unruly elements" were arrested for attacking the embassy with petrol bombs and rocks. A prosecutor said 40 people were held.
"The unjustly spilled blood of this oppressed martyr will no doubt soon show its effect and divine vengeance will befall Saudi politicians," Iran's Supreme Leader Ayatollah Ali Khamenei was quoted as saying by Iran's state television.
Nimr, the most vocal critic of the dynasty among the Shi'ite minority, had come to be seen as a leader of the sect's younger activists, who had tired of the failure of older, more measured leaders to achieve equality with Sunnis.
His execution sparked angry protests in the Qatif region in eastern Saudi Arabia, where demonstrators denounced the ruling Al Saud dynasty, and in the nearby Gulf kingdom of Bahrain.
Relatives of Nimr, reached by telephone, said authorities have informed them that the body had been buried "in a cemetery of Muslims" and would not be handed over to the family.
Although most of the 47 men killed in the kingdom's biggest mass execution for decades were Sunnis convicted of al-Qaeda attacks in Saudi Arabia a decade ago, it was Nimr and three other Shi'ites, all accused of involvement in shooting police, who attracted most attention in the region and beyond.
Khamenei's website carried a picture of a Saudi executioner next to notorious Islamic State executioner 'Jihadi John', with the caption "Any differences?".
Iranian protesters upset over the execution of a Shiite cleric Sheikh Nimr al-Nimr in Saudi Arabia, set fire to the Saudi embassy in Tehran, while a group of Iranian security protect Saudi Arabia's embassy in Tehran, Iran, Sunday, Jan. 3, 2016.(AP) Source: AP
In Iraq, religious and political figures demanded that ties with Riyadh be severed, calling into question Saudi attempts to forge a regional alliance against Islamic State.
Iraq's top Shi'ite cleric Grand Ayatollah Ali al-Sistani described the executions as an "unjust aggression".
The US State Department said Nimr's execution "risks exacerbating sectarian tensions at a time when they urgently need to be reduced", a sentiment echoed by EU foreign policy chief Federica Mogherini.
