RIYADH (AFP) - The Riyadh-led military coalition fighting Yemen's Houthi rebels declared a two-week ceasefire in the country starting on Thursday (April 9) in a bid to combat the spread of the deadly coronavirus, a Saudi official said.

The unilateral ceasefire follows an escalation in fighting between the warring parties despite a call by the United Nations for a ceasefire to protect civilians from the pandemic in the Arab world's poorest nation.

"We are announcing a ceasefire starting (Thursday) for two weeks," the official told reporters on Wednesday.

"We are expecting the Huthis will accept. We are preparing the ground to fight Covid-19" in Yemen.

The unilateral ceasefire will begin at 0900 GMT on Thursday (5pm Singapore time), he said.

There was no immediate reaction from the Iran-aligned rebels.

The coalition was committed to a two-week ceasefire but still reserved the right to defend itself if it came under attack, the Saudi official said.

The ceasefire may be extended if the Huthis respond "positively" to the gesture, he added.

The move was aimed at creating "favourable conditions" for a UN-supervised meeting between the Riyadh-backed Yemeni government, the rebels and the coaltion to pave the way for a permanent ceasefire in Yemen, coalition spokesman Turki al-Maliki said.

It was an opportunity to reach "a comprehensive and lasting cease-fire in Yemen", Maliki said in a statement released by the official Saudi Press Agency.

The Saudi-led military coalition has been active in Yemen's conflict in support of an internationally recognised government since 2015.

Yemen's broken healthcare system has so far recorded no cases of the Covid-19 illness, but aid groups have warned that when it does hit, the impact will be catastrophic.

The country is already gripped by what the UN calls the world's worst humanitarian crisis.

Saudi Arabia, the Yemeni government and the Huthi rebels had all welcomed an appeal from UN Secretary General Antonio Guterres for an "immediate global ceasefire" to help avert disaster for vulnerable people in conflict zones.

But fighting recently escalated again between the Huthis and Riyadh-backed Yemeni troops around the strategic northern districts of Al-Jouf and Marib, ending a months-long lull.

And Saudi air defences intercepted Yemeni rebel missiles over Riyadh and the border city of Jizan late last month, leaving two civilians wounded in the curfew-locked capital, state media reported.

It was the first major assault on Saudi Arabia since the Huthi rebels offered last September to halt attacks on the kingdom after devastating assaults on Saudi oil installations.

Last week, the coalition carried out multiple air strikes on Yemen's rebel-held capital Sanaa in retaliation for the missile strikes.