Deutsche Welle - As Islamabad is becoming increasingly wary of an escalating conflict between Saudi Arabia and Iran, Pakistani Prime Minister Imran Khan has set out on a mission to defuse tension between the Middle Eastern rivals.

Pakistani Prime Minister Imran Khan held talks with Iranian President Hassan Rouhani in Tehran on Sunday. He was also scheduled to meet with Iran's Supreme Leader Ayatollah Ali Khamenei and other high-ranking Iranian officials.

The purpose of his Iran visit, according to Pakistan's government, is to "promote peace and security in the region."

It is Khan's second visit to Iran this year.

"I told Prime Minster Imran [Khan] we welcome any gesture by Pakistan for peace in the region and appreciate his visit to our country," said Rouhani at a joint press conference with the Pakistani premier.

Rouhani said that among other things, they also discussed the Yemen war and the US sanctions on Iran.

"Regional issues have to be resolved through regional means and dialogue. We also emphasized that any goodwill gesture will be responded with a goodwill gesture and good words," said the Iranian president.

Pakistan's own worries

Khan was also expected to visit Saudi Arabia, Pakistan's main ally in the Middle East, after concluding his Iran trip.

During his visit to the US last month, Khan said that President Donald Trump had asked him to "mediate" between its ally Saudi Arabia and Tehran. The US leader, however, refuted Khan's claim.

Read more: Convincing Trump on Kashmir � Pakistani PM Khan's toughest diplomatic test

Nonetheless, Islamabad is stepping up efforts to defuse tensions between the Gulf neighbors as it fears that a possible US-backed war with Iran would spill over to Pakistani borders, unleashing sectarian violence between the country's majority Sunni and the minority Shiite populations and devastating its already frail economy due to a potential oil crisis.

Read more: US to send troops, missile defense system to Saudi Arabia after drone attack

"Pakistan attaches high importance to bilateral ties with Iran," Khan was quoted as saying by his Pakistan Tehreek-e-Insaf (Movement for Justice) party. "Pakistan is willing to play its role towards strengthening peace and stability in the region."

Militant activities

For years, ties between Iran and Pakistan have remained tense due to a deep bilateral mistrust. Pakistan has generally tried to maintain close ties with both Saudi Arabia and Iran � bitter regional foes � but has drifted away from Tehran in the past few years.

Both Islamabad and Tehran accuse each other of backing separatist groups, which are active in Pakistan's and Iran's Baluchistan provinces and seek independence from both countries.

In March, President Rouhani demanded Pakistan act decisively against anti-Iranian terrorists, following a February attack that killed 27 members of the elite Revolutionary Guards in Sistan-Baluchistan. Iran claimed that a Pakistani suicide bomber was behind the attack, which was claimed by the Sunni jihadist group Jaish al-Adl (Army of Justice), which Tehran says operates mostly out of Pakistan.

Read more: Why did US declare an anti-Iran militant group terrorist?

Shiite-majority Iran is wary of Islamabad's alleged support to various Sunni militant groups, which have been involved in launching attacks in Iran's eastern areas, and massacring Shiite citizens inside Pakistan.

The sectarian strife in Pakistan has been ongoing for some time now, with militant Islamist groups unleashing terror on the minority Shiite groups in many parts of the country. Most of these outfits, including the Taliban, take inspiration from the hardline Saudi-Wahabi Islamic ideology.

'Solidly allied with Riyadh'

Iran is also angered by Pakistan's role in the Saudi-led military alliance that is operating against Shiite Houthi rebels in Yemen.

Read more: Pakistan's Yemen dilemma: Being neutral is not an option

"It is obvious that the Pakistani-Iranian ties have not been cordial for quite some time. However, if the Pakistani government gives more importance to Saudi Arabia in the Yemen conflict, the relations will likely get acrimonious," said Tariq Peerzada, a foreign affairs expert in Islamabad.

Read more: Examining Saudi-Pakistani ties in changing geopolitics

Islamabad's over-enthusiasm to please Riyadh could further exacerbate its relations with Tehran. Security analysts say that Pakistan's support to Saudi Arabia has increased the Sunni-Shiite rift in the South Asian country. They also say that Sunni militant groups feel further emboldened by the fact that Raheel Sharif, Pakistan's ex-army chief, now heads the Saudi-led military alliance.

Tehran is aware of Islamabad's cooperation with Riyadh. At the same time, it is aware of the concerns and limitations of its ties with Pakistan and wants to maintain "normal" relations with the neighboring country.

"Pakistan remains solidly allied with Saudi Arabia, regardless of how intense the outreach may be from Tehran. There are decades of close military cooperation that are not about to undone," said Michael Kugelman, a South Asia expert at the Washington-based Woodrow Wilson Center for Scholars.

It remains to be seen whether Pakistani leader Khan could convince Iranian authorities that his country would not undermine Tehran's interests in the region. But experts say that since Pakistan is already part of the Saudi security alliance and has not done enough to allay Iran's concerns about its alleged role in backing anti-Iran militants on its soil, Khan's diplomatic efforts in Tehran are unlikely to yield results.