ISLAMABAD, April 16 (Xinhua) -- Diplomatic activity intensified on Wednesday around the ongoing U.S.-Iran conflict, as Pakistan stepped up mediation efforts amid prospects for renewed negotiations.

A high-level Pakistani delegation led by the country's Army Chief Asim Munir arrived in Tehran as part of Islamabad's continued efforts to facilitate dialogue between Washington and Tehran. The delegation, comprising senior officials from security and diplomatic institutions, is carrying key messages linked to the next phase of engagement between the two sides.

The visit follows earlier face-to-face talks hosted in Islamabad that ended without agreement, but kept diplomatic channels open. Iranian officials confirmed that exchanges with the United States are continuing through Pakistan.

The diplomatic push coincides with broader regional outreach by Pakistan's leadership. Prime Minister Shehbaz Sharif arrived in Jeddah on an official visit to Saudi Arabia. Later this week, he will also travel to Qatar and Trkiye, where discussions are expected to focus on bilateral ties as well as regional peace and security.

Despite these efforts, key differences between the United States and Iran remain unresolved. U.S. President Donald Trump said the conflict was "very close" to completion, while also indicating that a new round of talks with Iran could take place soon, potentially in Pakistan.

Iran, meanwhile, has taken a cautious position. Iranian Foreign Ministry spokesperson Esmail Baghaei said no agreement has been reached on extending the current ceasefire, rejecting media reports suggesting otherwise. While expressing openness to discussing parameters of its nuclear program, Baghaei has reiterated its right to peaceful nuclear energy and called for sanctions relief as part of any broader settlement.

Although diplomatic engagement continues, no timeline has been set for the next round of talks.

Meanwhile, tensions on the ground continue to pose risks to regional stability. The United States has imposed a naval blockade targeting Iranian maritime trade, with U.S. military officials claiming that economic activity linked to Iran by sea has been effectively halted within a short period. The move has heightened tensions in key strategic waterways.

In response, Iranian military officials warned of possible countermeasures. Ali Abdollahi, chief commander of Iran's main military command Khatam al-Anbiya Central Headquarters, said Iran could block trade flows across major maritime routes, including the Strait of Hormuz, the Gulf, the Sea of Oman and the Red Sea, if restrictions on its shipping persist.

As diplomatic channels remain active but inconclusive, Pakistan's mediation efforts -- alongside parallel regional and international initiatives -- are likely to play a key role in shaping whether the current pause in fighting can evolve into a broader and lasting settlement.