Around 100 Saudi-led ground troops have arrived in the Yemeni port of Aden.
Saudi Arabia denies they are the vanguard of a ground invasion.
The Saudi Arabian air assault on Yemen is aimed at removing the Houthi militia that has taken control of the capital.
The Saudi leadership said the air strikes would be followed by a ground invasion.
But the strikes have failed to dislodge the Houthis. And plans for an invasion appeared to be faltering.
At least 1,200 people have died in air strikes, and the war has displaced thousands more.