UK declines to join US naval blockade on Iranian ports

The UK Treasury Minister confirmed the UK will not participate in the US naval blockade of Iranian ports. The likelihood of the US lifting the blockade by May 31 sits at 83.5% YES, up from 79% 24 hours ago.

The UK’s refusal signals weak international backing for the US-led blockade. The April 19 sub-market sits at 25% YES, dragged down by the UK’s stance and what it means for the blockade’s viability. The 58-point jump between the April 19 and May 31 odds tells us traders expect something to break in that window.

In the warships through the Strait of Hormuz market, odds of the UK sending warships are at 8.5% YES, consistent with the UK’s refusal to participate militarily.

Daily actual USDC volume is $30,880 across all blockade-related markets. It takes $1,902 to move the May 31 odds by five points, which points to moderate liquidity. The largest single move was a 4-point spike at 4:11 AM, showing some price sensitivity to news flow.

The UK’s decision could be noise rather than a fundamental shift. But the gap in international support may pressure the US to reconsider. At 84¢, a YES share pays $1 if the blockade is lifted by May 31, a 1.19x return. That bet requires a diplomatic breakthrough or strategic shift within 46 days.

Watch for Trump’s statements on social media or official channels, and any shifts in NATO or US naval posture. These are the main indicators for where these markets move next.

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