US Secretary of State Rubio said Iran is pursuing intercontinental ballistic missiles and called Tehran’s refusal to discuss them a “big, big problem.” Talks Thursday will focus on the nuclear programme, though he stressed diplomacy remains on the table.Summary:Rubio calls Iran a “very grave” US threatSays Iran not enriching currentlyWarns Tehran seeking enrichment capabilityTalks Thursday to focus on nuclear programmeSays Iran pursuing intercontinental ballistic missilesMissile issue a “big, big problem”Flags conventional weapons riskDiplomacy “never off the table”US Secretary of State Marco Rubio described Iran as a “very grave threat” to the United States, adopting a firm tone ahead of renewed talks expected to centre on Tehran’s nuclear programme.Speaking on Wednesday, Rubio said Iran is not currently enriching uranium but is attempting to reach the point where it ultimately can. The comment suggests Washington believes Tehran may be positioning itself to retain the technical capacity for rapid enrichment, even if active production is presently limited. That assessment keeps the focus squarely on preventing a scenario in which Iran could quickly scale up nuclear activity.Rubio confirmed that Thursday’s discussions will be largely focused on the nuclear issue. However, he made clear that the United States views the challenge as broader than enrichment alone. He warned that Iran is attempting to develop intercontinental ballistic missiles and possesses conventional weapons systems designed to threaten American interests. Significantly, he characterised Iran’s insistence on not discussing ballistic missiles as a “big, big problem,” signalling that missile development could become a central friction point in negotiations.The remarks underscore Washington’s view that missile capability and nuclear capacity are strategically linked, even if talks are formally structured around the nuclear file. By highlighting ICBM development, Rubio elevated the security stakes beyond the regional level.At the same time, he sought to temper expectations of imminent confrontation. Rubio stressed that diplomacy is “never off the table” and described Thursday’s engagement as simply “the next opportunity to talk,” rather than a decisive moment.Taken together, the comments reflect a dual-track posture: sustained pressure and deterrence messaging alongside continued willingness to engage diplomatically. This article was written by Eamonn Sheridan at investinglive.com.