Iran has accused Saudi Arabia of launching an air strike on its embassy in the Yemeni capital of Sana'a.

According to Iranian state-run TV channels a number of embassy guards were injured in the alleged missile attack.

The IRIB news channel quoted an Iranian foreign ministry spokesman, Hossein Jaber Ansari, as saying: "Saudi Arabia is responsible for the damage to the embassy building and the injury to some of its staff."

Speaking to the Reuters news agency, a spokesman for the Saudi-led coalition in Yemen said it was investigating Iran's claim.

He confirmed heavy air strikes were carried out in Sana'a on Wednesday night, but said they were targeting Houthi missile launchers.

Brigadier General Ahmed Asseri said the coalition had requested the coordinates of all current diplomatic missions in Yemen and implied Iran's accusation came via Houthi sources, who he said "have no credibility".

Earlier, Iran accused Saudi Arabia of using cluster bombs in a series of air strikes on Thursday which, it said, killed five people.

The claims come amid escalating tensions between the two Middle East powers, after the execution of a prominent Shia cleric in Saudi Arabia and the subsequent ransacking of the Saudi embassy in Tehran.

Saudi Arabia is militarily backing the ousted Sunni-led government in Yemen, while Iran backs the Shia Houthi rebels.