"RESTORING HOPE"
Saudi Arabia said a new phase called "Operation Restoring Hope" would now begin in which political, diplomatic and military action would be combined but the main focus would be on the political process and aid efforts.
The conflict has created severe shortages of food and other supplies by closing sea and airports. The World Health Organization said on Tuesday that 944 people were reported killed and 3,487 wounded in Yemen in the month up to Friday.
The United States said on Monday an aircraft carrier and guided-missile cruiser had gone to waters off Yemen to join seven other US warships already in the area.
The Pentagon said the ships were there to ensure freedom of navigation through the area, which is vital to oil shipping and controls approaches to the Red Sea and the Suez Canal.
It said the ships were also watching a flotilla of Iranian cargo vessels that had approached Yemen.
President Barack Obama warned Iran on Tuesday not to send weapons to Yemen that could be used to threaten shipping traffic in the region.
Iran called for all sides in Yemen's conflict to start negotiations, saying long-term peace was possible.
"History has demonstrated that military intervention is not a proper response to these crises and will instead exacerbate the situation," Iran's President Hassan Rouhani said at an Asian-African conference in Jakarta.
The United States and Saudi Arabia have accused Shi'ite Iran of arming the Houthis, a claim Iran denies.