A lightning offensive by the Iran-aligned Houthis has put the group in a position to control a crucial Middle East waterway, creating a major new problem for US President Donald Trump as his war with Iran grinds on in its seventh month, Reuters notes.

The fighters reached the island of Perim on Friday, in the middle of the strait between Yemen and Africa. That is bad news for Saudi Arabia, which has been shipping much of its oil from Red Sea ports since the war effectively closed the Strait of Hormuz, on the opposite side of the Arabian Peninsula.

It also comes at a difficult time for Trump, who is already grappling with record-low approval ratings and searching for a way out of the conflict, most recently by announcing an economic pressure campaign designed to force concessions from Iran’s government.

High US gasoline prices driven by the conflict have jeopardised his Republican Party’s chances of keeping control of Congress in the November midterm elections. Iran remains defiant despite being hurt militarily and economically.

“Just weeks ago, Trump adopted a strategy of squeezing Iran’s economy while keeping military conflict at levels too low to squeeze the American economy,” said Stephen Wertheim, a senior fellow at Carnegie Endowment for International Peace.

“The Houthis have shattered Trump’s plan.”

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