Senegal is to send 2,100 troops to support the Saudi-led campaign in Yemen, its foreign minister says.
Mankeur Ndiaye said Senegal was responding to a Saudi request to help secure the kingdom's border with Yemen.
Meanwhile, the Saudi foreign minister said his country was considering temporary truces to allow for aid to be delivered in specific areas.
A Saudi-led coalition has been carrying out air strikes against Yemen's Houthi rebels, who seized the capital, Sanaa.
President Abdrabbuh Mansour Hadi fled and the declared aim of the Saudi-led campaign is to restore him.
Foreign Minister Ndiaye told Senegal's parliament that the coalition was "aiming to protect and secure the holy sites of Islam, Medina and Mecca", Reuters reported.
Countries participating in Yemen military campaign
- Saudi Arabia
Senegal is a majority Sunni Muslim country that has received aid from Saudi Arabia. But there was swift criticism of the announcement in Senegal.
"Saudi Arabia isn't threatened and neither are Islam's holy sites. There is nothing to justify a military intervention by Senegal," opposition politician Modou Diagne was quoted as saying.
The coalition includes eight Arab states. The US, the UK and France are providing logistical support.
More than 1,200 people have been killed and 300,000 have fled their homes in the past six weeks, according to the UN. It has warned repeatedly that Yemen faces a severe humanitarian crisis.
On Monday air strikes were reported at the airports in Sanaa, in Hodeida in the west, and in the southern city of Aden, prompting criticism from the UN.
"I strongly urge the coalition to stop targeting Sanaa international airport and to preserve this important lifeline - and all other airports and seaports - so that humanitarians can reach all those affected by the armed conflict in Yemen," said humanitarian co-ordinator Johannes Van Der Klaauw.
Fighting on the ground between rebels and allies of Mr Hadi is continuing.