Iran dispatched a naval frigate to the Red Sea amid an escalating standoff between Western nations and Tehran-backed militants that has seen maritime traffic attacked by drones, missiles and speedboats.

Iran’s Tasnim news agency reported that the warship Alborz crossed the Bab el-Mandeb Strait and entered the busy waterway, where a U.S.-led coalition is already stationed. According to Iranian officials, the 51-year-old vessel, originally sold to the shah of Iran by Britain, will supervise naval missions in the Indian, Pacific and Atlantic oceans.

The move adds Iran’s military into an increasingly volatile crisis unfolding in the Red Sea, where tensions have soared in the wake of the Israel-Hamas war in the Gaza Strip. 

Houthi rebels from Yemen — who, along with Gaza-based Hamas, form part of the Iranian-backed “axis of resistance” against Israel — started targeting commercial vessels traversing the Red Sea in December. The group insists it aims only to disrupt tankers and cargo liners linked to Israel, but dozens of civilian vessels have been put at risk.

On Monday, U.K. Defense Secretary Grant Shapps hinted in an op-ed published in the Telegraph that London was ready to launch air strikes against the Houthis. 

In December, the U.S. announced an international security effort dubbed Operation Prosperity Guardian to police the Red Sea. The U.K. deployed a naval destroyer as part of the coalition, and Denmark said Friday it would send a frigate to join the operation.

The EU agreed to join the U.S. effort but countries such as France and Spain announced their military vessels in the region would remain under national control. 

“We’re keeping a French command in this affair and we’re continuing to act in self-defense,” French Armed Forces Minister Sébastien Lecornu told French TV on Tuesday. 

The French Languedoc FREMM multipurpose frigate is currently in the region, a French official said. 

The Red Sea is a vital thoroughfare for shipborne cargo and energy exports. 

Via Politico