US Secretary of State John Kerry has warned Iran over its alleged support for Houthi rebels in Yemen.
He said the US would support any state in the Middle East that felt threatened by Iran, and would not “stand by” if Iran destabilised the region.
The US is backing a Saudi-led coalition seeking to drive back the rebels and restore President Abdrabbuh Mansour Hadi, who fled the country last month.
Iran has denied accusations it is providing military aid to the Houthis.
However, it despatched two navy vessels to the Gulf of Aden, off the southern coast of Yemen, on Wednesday.