Iranian President Masoud Pezeshkian traveled to Pakistan on Saturday and Sunday, a visit in which he and Pakistani Prime Minister Shehbaz Sharif agreed to boost bilateral relations.

The leaders signed deals to increase trade to $10 billion (€8.6 billion) and boost their security ties.

Both countries face security challenges related to militant activity near their border, where groups such as Jaish Al-Adl in Iran and the Pakistan-based Balochistan Liberation Army (BLA) have carried out numerous attacks.

"Iran appears to be shifting toward security diplomacy rather than confrontation. Tehran is actively seeking intelligence-sharing mechanisms, joint border patrols, and other forms of coordinated security engagement with Islamabad," Fatemeh Aman, senior fellow at the Washington-based Middle East Institute, told DW.

Pakistan and Iran share a 900-kilometer (560-mile) border that runs through Balochistan, a region which comprises the Pakistani province of the same name and the Iranian province of Sistan and Baluchestan, as well as parts of Afghanistan.

The region has struggled for decades with a separatist insurgency on both sides of the border. Iran and Pakistan have a strategic alliance fighting those militant groups, but their relationship has at times been strained due to the cross-border terrorism, which resulted in clashes and tit-for-tat missile strikes last year.

Despite those issues, relations between Iran and Pakistan remain largely amicable. Pakistan sided with Iran during the recent 12-day conflict with Israel, condemning Israeli strikes on Iranian nuclear facilities and clearly labeling Israel as the aggressor.

But even with that show of support, Pakistan's growing partnership with the United States — whose ties with Iran have been marked by decades of hostility and tensions, especially over Iran's nuclear program — could become a cause for concern in Tehran.

Aman said that "despite its history of close ties with Washington, Pakistan has consistently avoided direct military alignment when it comes to Iran."

Because of their strategic ties, "Tehran views Islamabad as unlikely to serve as a military platform for hostile actions against Iran," she added.

US-Pakistan partnership

US President Donald Trump last week said the US had agreed with Pakistan to develop the South Asian nation's oil reserves — much of which are reportedly in Balochistan — which could see the US extend its influence on Iran's eastern borders.

The region is also of interest to the US because of its geographic location, abundant natural resources, and proximity to Iran and Afghanistan.

"Iran may be wary of American presence along its border if US companies arrive in Balochistan to explore oil prospects. But then Pakistan has also had reservations about Indian presence in Chabahar [an Iranian port city being developed with Indian investment], so the feeling is mutual," Osama Malik, an expert on trade law, told DW.

Muhammad Shoaib, an International affairs expert and Assistant Professor at Quaid-i-Azam University Islamabad, pointed out that the US-Pakistani relationship has been marked by alliances during the Cold War and the War on Terror as well as tensions over Pakistan's counterterrorism efforts and its relationship with militant groups.

"Since Iran has witnessed periods of Pakistan's relationship with the US, it is not worried about the recent opening between Pakistan and the US," Shoaib told DW.

Even though the US-Pakistan relationship appears to be growing closer, it is far from straightforward.

Pakistan nominated Trump for the Nobel Peace Prize "in recognition of his decisive diplomatic intervention and pivotal leadership during the recent India-Pakistan crisis," but less than 24 hours later, Islamabad condemned US airstrikes on Iranian nuclear facilities.

Iran seeking Pakistan's help

"At a time when the possibility of Israeli or US military action against Iran appears increasingly real, Tehran is seeking to improve its ties with Pakistan," said Aman of the Middle East Institute.

She believes that Iran expects Pakistan to continue supporting its right to a peaceful civilian nuclear program.

Pakistan finds itself in a politically sensitive and diplomatically precarious situation, both working to bolster its strategic relationship with the US while maintaining its support of its Muslim neighbor.

"Iran needs a credible conduit to Washington, something Pakistan has a proven record of. Pakistan can, and has reportedly been playing, a role between Iran and the US. Pakistan supports Iran's right to a peaceful, civilian nuclear program but it does not extend any support for Iran getting nuclear weapons," said Shoaib.

After a meeting last month in Washington with Pakistani Foreign Minister Ishaq Dar, US Secretary of State Marco Rubio praised Pakistan's commitment to mediating between Washington and Tehran and preserving regional stability.

"Islamabad is willing to contribute positively toward easing tensions between Iran and the US," Pakistan's Foreign Ministry spokesperson Shafqat Ali Khan told DW.

Trade law expert Malik believes that "Iran would like Pakistan to use its newfound closeness to Trump to help it secure a civilian nuclear deal."

US sanctions stymie bilateral trade

US sanctions on Tehran over its nuclear program are a major sticking point preventing full-scale bilateral trade between Pakistan and Iran.

International affairs expert Shoaib said Islamabad has avoided formal trade with Iran — including the Iran-Pakistan gas pipeline project — due to the sanctions, highlighting that Islamabad will want "some sort of easing of US sanctions on Iran" if it is to pursue a more comprehensive trade relationship.

"Pakistan already conducts off-the-books trade with Iran and, according to some estimates, 30% of Pakistan's fuel consumption is covered by smuggled Iranian oil. Easing tension between Tehran and Washington through Pakistan could ease US sanctions," trade lawyer Malik said.

But until sanctions are eased, major projects like the gas pipeline remain effectively frozen, according to analyst Aman.

"The pipeline is unlikely to be revived under current conditions, as Islamabad cannot afford to risk secondary sanctions or further strain its relationship with Washington," she said.

Edited by: Karl Sexton