Iran has sent its Alborz warship to the Red Sea as tensions flare over Tehran-backed Houthis targeting vessels.

There is little information about the Alborz's mission but the semi-official Tasnim news agency revealed Iranian warships had been operating in open waters to secure shipping routes, combat piracy and carry out other tasks since 2009.

Iran's decision to send a warship to the area comes after Yemen's Iran-backed Houthis started targeting ships in November.

The decision to target vessels came as the group hoped to show their support for the Palestinian Islamist group Hamas in its war with Israel.

Houthi militants attacked a Maersk container vessel on Saturday and Sunday.

The incident prompted the company to pause all sailing through the Red Sea for 48 hours.

Iran's navy chief Shahram Irani last month revealed the Alborz was carrying out missions in the Red Sea.

Tehran's Defence Minister Mohammad Reza Ashtiani also stressed "nobody can make a move in a region where we have predominance".

Foreign Secretary Lord David Cameron took aim at Iran over its involvement in the incident.

He said: "I made clear that Iran shares responsibility for preventing these attacks, given their long-standing support to the Houthis."

Defence Secretary Grant Shapps added: "This morning’s atrocious attacks by the Iranian-backed Houthis were an unacceptable and outrageous act designed to destabilise global trade.

"The Houthis must end their illegal campaign against merchant shipping and stop all violent attacks immediately."

A stock image of an Iranian warship