WASHINGTON: US Secretary of State Marco Rubio said on Thursday there were “some good signs” that a possible agreement with Iran could be reached, as mediator Pakistan intensified diplomatic efforts to end the US-Iran conflict through dialogue and diplomacy.
Rubio said Washington remained open to diplomacy with Iran, while warning that other options were available if talks failed.
“The president’s preference is to do a good deal, that’s his preference. It’s always been his preference,” Rubio told reporters.
“There are some good signs, but … I don’t want to be overly optimistic.”
Rubio added that Pakistani officials were travelling to Tehran on Thursday. “So hopefully that will advance this further,” he said.
Rubio voiced hope that Pakistan’s ongoing diplomatic efforts would advance diplomacy on ending the US-Iran war, saying there has been progress.
Rubio also warned that any move by Iran to impose tolls in the Strait of Hormuz would make a deal “unfeasible”.
.@SecRubio on Iran: “@POTUS‘s preference is to do a good deal… I’m not here to tell you that it’s going to happen for sure, but I’m here to tell you that we’re going to do everything we can to see if we can get one. If we can’t get a good deal, @POTUS has been clear — he has… pic.twitter.com/dhah7hSlvV
— Rapid Response 47 (@RapidResponse47) May 21, 2026
Tensions over the Strait of Hormuz remained central to the conflict.
Iran’s Islamic Revolutionary Guard Corps (IRGC) said 31 vessels transited the Strait of Hormuz in the past 24 hours “with the coordination and security of the IRGC Navy”, according to a statement carried by the semi-official Tasnim News Agency.
Meanwhile, US Central Command (CENTCOM) said 94 commercial vessels had been redirected from Iranian ports and four others disabled amid what it described as an American naval blockade, in a post on X.
As of May 21, CENTCOM forces have redirected 94 commercial vessels and disabled 4 while enforcing the blockade to prevent the flow of commerce into and out of Iranian ports. pic.twitter.com/A54jjxDaYE
— U.S. Central Command (@CENTCOM) May 21, 2026
Iran has also defined a “management zone” in the Strait of Hormuz, spanning from the eastern to western entrances of the waterway.
It said transit through the area would require coordination and authorisation from Iranian authorities.
Pakistan intensifies diplomatic efforts
Pakistan, which is playing a key role as a mediator, intensified diplomatic engagement as part of efforts to revive US–Iran talks.
Iranian President Masoud Pezeshkian met Pakistan Interior Minister Mohsin Naqvi in Tehran on Wednesday to discuss regional developments and ongoing indirect negotiations between Iran and the United States, Iran’s Fars news agency reported.
Iran Cautions of US, Israeli Plot to Divide Islamic Stateshttps://t.co/xjIiEvCaG8 pic.twitter.com/2ahlmo7pZi
— Fars News Agency (@EnglishFars) May 18, 2026
Both sides reviewed diplomatic consultations aimed at regional stability and security, and emphasised continued dialogue and cooperation.
Naqvi conveyed Pakistan’s position on supporting negotiations and mutual understanding, according to Iranian media reports.
Pezeshkian thanked Pakistan for its role in promoting regional stability.
Trump willing to wait
US President Donald Trump said on Wednesday that Washington was willing to wait a few days for Iran’s response on a possible agreement.
“I’m willing to wait a few days for the right answer from Iran. They are logical people,” Trump told reporters.
“If we don’t get the right answers, it will move very quickly. We are all ready to go,” he added.
.@POTUS on Iran: "It's right on the borderline, believe me. If we don't get the right answers, it goes very quickly. We're all ready to go. We have to get the right answers — it would have to be a complete 100% good answers." pic.twitter.com/LGFDQW4Z3h
— Rapid Response 47 (@RapidResponse47) May 20, 2026
Trump rejected suggestions that sanctions relief on Iranian oil exports had been offered, saying: “I’m not doing any relief until they sign an agreement.”
He said any deal would require “100 per cent good answers” from Tehran.
Iran reviewing latest US proposal
On Wednesday, Iranian Foreign Ministry spokesman Esmaeil Baghaei said Tehran had received a new US proposal through mediators and was reviewing it.
According to Iran’s Tasnim News Agency, Baghaei said Iran was “pursuing the path of negotiations with seriousness and good faith”, despite what he described as “strong and reasonable suspicion” about Washington’s intentions.
Iranian President Pezeshkian also reiterated that diplomacy remained open.
“All paths remain open from our side,” he wrote on X. “Mutual respect in diplomacy is far wiser, safer, and more sustainable than war.”
Russia and China call for diplomatic solution
Russia said the Iran crisis could only be resolved through diplomacy that takes Iranian interests into account.
Russian Foreign Ministry spokeswoman Maria Zakharova said only Iran should decide the fate of its uranium reserves, according to remarks at a briefing.
🔴 #LIVE: Briefing by Russian Foreign Ministry Spokeswoman Maria Zakharova on topical foreign policy issues https://t.co/g0poSOsDNv
— MFA Russia 🇷🇺 (@mfa_russia) May 21, 2026
China, meanwhile, confirmed that Pakistan’s Prime Minister Shehbaz Sharif would visit Beijing later this month.
A foreign ministry spokesperson said China would work with Pakistan to “make positive contributions to the early restoration of peace and stability in the Middle East”.
