Saudi Arabia's air defences intercepted a missile fired by Houthi rebels on the same day that the Iran-backed insurgents targeted a hospital in Yemen.

The missile, the latest in a series of similar attacks, was directed towards Najran city in the southwest of the country.

Colonel Turki Al Maliki, the spokesman for the Saudi-led coalition in Yemen, said the missile had been launched to target civilian and populated areas.

Fragments of the missile were scattered over residential areas although no injuries were reported.

Elsewhere on Friday, Houthi militia shelled a hospital in the country's Red Sea coastal region.

''No casualties were reported among the hospital staff,'' medical sources said.

A Saudi-led coalition, which includes the UAE, intervened in March 2015 at the request of the legitimate government of Yemeni President Abdrabu Mansur Hadi.

The Houthis have repeatedly fired missiles at Saudi Arabia, which the United States and UN experts say are of Iranian origin, a claim Tehran denies.

Coalition and Yemeni forces have made territorial gains in recent months against the Houthi rebels in an armed push moving northward from the Bab Al Mandab strait towards Al Hodeidah on the Red Sea, where 80 per cent of Yemen's crucial food imports arrive.