Despite several moments when the two sides appeared close to a deal, key disagreements have repeatedly prevented a resolution, according to Al Jazeera.

Although large-scale hostilities eased following a Pakistan-mediated ceasefire that took effect on April 8, diplomatic efforts have repeatedly faltered amid disagreements over Iran’s nuclear programme, sanctions, regional security issues and freedom of navigation in the Gulf.

Islamabad talks raise hopes

The closest the two sides came to direct engagement was during talks held in Islamabad on April 11 and 12, marking the first face-to-face negotiations between US and Iranian officials since Iran’s 1979 revolution.

The US delegation was led by Vice President JD Vance, while the Iranian side included Foreign Minister Abbas Araghchi and other high-ranking officials.

Before the talks began, Iran made it clear that a ceasefire in Lebanon and the unfreezing of its overseas assets were non-negotiable conditions for any progress.

Prime Minister Shehbaz Sharif, whose government was acting as the main mediator, called the meeting a turning point for peace in the region.

However, the negotiations ended without an agreement.

Later, Iranian officials expressed a willingness to continue discussions, but the US delegation chose to bring the talks to a close.

Washington later said Tehran had failed to provide sufficient assurances regarding its nuclear ambitions.

Iran maintains that its nuclear programme is intended solely for civilian purposes, while the US and its allies argue that Tehran’s stockpile of highly enriched uranium raises concerns about potential weapons development.

Analysts say disagreements over both the substance and timing of a possible nuclear agreement remain major obstacles.

Naval blockade escalates tensions

Any momentum generated by the Islamabad talks quickly dissipated when Washington announced a naval blockade of Iranian ports days later, aiming to curb Tehran’s oil revenues.

The US naval blockade move complicated diplomatic efforts to resolve the crisis.

Lebanon ceasefire fails to hold

Hopes for de-escalation emerged on April 16 when US President Donald Trump announced that a 10-day ceasefire had been reached between Israel and Lebanon to facilitate negotiations.

The development was seen as particularly significant because Tehran has repeatedly linked progress in wider peace talks to an end to Israeli military operations in Lebanon.

But optimism faded as Israeli strikes continued despite the ceasefire announcement.

Humanitarian organisations reported hundreds of deaths in the weeks that followed, while Iran maintained that lasting peace in Lebanon remained a non-negotiable demand.

Strait of Hormuz dispute deepens divide

Another potential opening emerged when Iran signalled it would ease restrictions on commercial shipping through the Strait of Hormuz, one of the world’s most important energy transit routes.

Iranian Foreign Minister Abbas Araghchi announced that commercial vessels would be allowed to pass freely during the ceasefire period, prompting hopes of reduced tensions in the Gulf.

The United States has insisted that sanctions and its naval blockade of Iranian ports will stay in place until a wider peace agreement is reached.

Tehran, in turn, warned that if its own vessels were restricted, foreign ships would face similar obstacles.

Disputes over control and access to the strategic Strait of Hormuz have since become a major sticking point in negotiations.

Tensions flared again in early June after reports of a tense phone call between President Trump and Israeli Prime Minister Benjamin Netanyahu over Israeli military operations in southern Lebanon.

Trump reportedly expressed frustration over Israel’s actions at a time when talks with Iran were still fragile.

For a brief moment, there was hope that the US might pressure Israel to halt its campaign, potentially opening a window for diplomacy with Tehran.

But Israeli operations continued, including air strikes and displacement orders in several southern towns, dashing expectations of a breakthrough.

Analysts say these repeated setbacks underline the conflict’s complexity: progress on one front is often offset by deadlock on another.