YEMEN’S national airline has cancelled all flights to the country’s only two functioning airports after the Saudi-led coalition fighting to oust Houthi rebels announced the closure of all land, air and sea ports.

The tightening of an embargo in place since 2015 came after a ballistic missile fired by the Houthis on Saturday at an international airport on the outskirts of the Saudi capital was intercepted.

The missile strike has further stoked tensions between regional rivals Shiite Iran and Sunni Saudi Arabia, whose coalition blamed Iran for Saturday’s strike, saying it could be “considered as an act of war”.

However, Iran, which supports the Houthi government, has denied arming the rebels who say their Volcano-variant missile is locally produced.

“Iran’s role and its direct command of its Houthi proxy in this matter constitutes a clear act of aggression that targets neighbouring countries, and threatens peace and security in the region and globally,” a coalition statement said.

Iran’s foreign ministry spokesman Bahram Ghasemi dismissed the allegations as a “lie”.

The port closures could further limit access for the delivery of humanitarian aid to the Arab world’s poorest country, which has been devastated by more than two years of a bombing campaign by the coalition which has killed more than 10,000 civilians.

The coalition said the closures would be temporary and “take into account” the work of aid organisations.

Yemenia airlines said yesterday the coalition, which controls Yemen’s airspace, had declined permission to fly out of Aden and Sayoun.

Yemen’s main international airport, in the rebel-held capital, Sanaa, has been closed since August 2016 by order of the coalition.

The rebel-held north has largely relied on the Red Sea port of Hodeida for humanitarian aid and fuel supplies. A full blockade of the port would cut off a lifeline for the Houthis, as well as civilians.

It is not yet clear whether any supplies will be allowed to enter via land crossings with Saudi Arabia and Oman.