Oil tanker traffic through the Strait of Hormuz should quickly increase if the United States and Iran reach a credible agreement, says Frontline CEO Lars Barstad reports CNBC News.

Mr Barstad said Gulf states are desperate to boost exports and tankers are positioned near the region to benefit from a reopening. Frontline has a fleet of 80 vessels, with five currently stuck in the Persian Gulf due to the closure.

Traffic will not return soon to prewar levels of 130 to 140 ships daily, but a deal could lift volumes above the current five to 10 ships crossing each day. About 10 per cent of the world's very large crude carriers are stuck in the Gulf, each carrying up to two million barrels, and would be the first to exit Hormuz once it reopens.

Mr Barstad noted some shipping companies are holding tankers near the Gulf as a commercial option, though uncertainty persists with US President Donald Trump repeatedly threatening escalation before pulling back. Shippers may eventually redeploy vessels if no deal materialises.

The Joint Maritime Information Center downgraded Hormuz's threat level from critical to severe on June 7, citing safe transits via the southern route near Oman. Mr Barstad said owners will move quickly once risk assessments ease further.

Iran and Oman have discussed imposing transit fees, which the US opposes. Mr Barstad said shippers dislike tolls but would adapt if required, noting similar charges apply at the Suez and Panama canals.