- US-led military action -

The most-talked-about option is for the US and willing allies to secure the 167-kilometre (104-mile) long passage militarily.

There are currently two US carrier strike groups -- naval formations built around an aircraft carrier -- in the region, the "bare minimum number of warships" required for an escort mission, Nick Childs, senior fellow at the IISS, told a seminar convened by the London-based defence think-tank.

Britain, France, Germany, Italy, the Netherlands and Japan on Thursday said they were ready "to contribute to appropriate efforts to ensure safe passage through the strait."

But it remains a daunting mission.

"This is not just a maritime issue, and escort ships will not solve the problem alone... it would need a whole wrap around it, of air capability, maritime capability, crewed, uncrewed, long-range strike, short-strike, et cetera," a UK defence official said in a briefing on Wednesday.

"It's a significant military challenge... This must be a multinational solution," the official added. "We're not anywhere near that at the moment."

- Diplomatic off-ramp -

A purely diplomatic solution remains on the table and is the preferred route for many global leaders.

Several governments are in bilateral talks with Tehran over an "emerging IRGC registration and vetting system", said Richard Meade, editor-in-chief of maritime intelligence journal Lloyd's List -- a reference to Iran's Revolutionary Guards.

The proposed system would create an Iranian-approved "safe corridor" for ships to use, Meade told an online briefing on Thursday.

"We know that several governments -- including China, but (also) India, Pakistan, Iraq, Malaysia -- they're all in direct talks with Tehran, coordinating vessel transits," he said.

At least nine ships have already used this corridor, which routes ships close to Iran's Larak Island for visual checks by Iranian authorities, he added.

While this offers some movement, Meade warned that "negotiated safe passage... is unlikely to dramatically increase the trickle of tonnage".

- Take the chance -

Another option is for shipowners to risk crossing the strait without dealing with Iran.

"Greek owners and operators have, typically, a higher risk appetite" and continue to move tankers through the route, Bridget Dyken, an analyst at analysis group Lloyd's List Intelligence, told the briefing.

Her colleague Cichen Shen added there was evidence of a potential Chinese exit plan where tankers pay a "7.5 percent of hull value" insurance rate for 72 hours of coverage to transit the strait.

- Muddle through -

Iran could continue to maintain a partial opening of the strait in the medium term, with opaque rules for transiting, Richard Luckyn-Malone of intelligence consultancy Herminius told the Marine Insurance London industry conference on Friday.

"Strategic ambiguity is absolutely fundamental to what they do, and it would very much serve Iran's purposes if this was where we sat," he said.

But he questioned whether "the world is actually going to sit still and accept the idea of the straits being ambiguously open for months and months."

- Wait it out -

Iran's Parliament Speaker Mohammad-Bagher Ghalibaf warned on Tuesday that "the Strait of Hormuz won't return to its pre-war status".

"Even in the best-case scenario, going back to a fully reopened status is several months away," Luckyn-Malone said.

"There's unexploded ordnance floating around. There may be minefields... and there's going to be nervous security forces on either side."