The Saudi air force has been launching strikes on Yemen, mainly Houthi dominated areas, since March 2015.
Twelve Saudi soldiers, including four officers, were killed on Tuesday when their helicopter went down in Yemen, the Arab coalition fighting Yemeni rebels said in a statement.
The statement said investigations were ongoing to determine the causes of the accident.
Yemen has been suffering from a brutal conflict between the government and the Houthi movement backed by army units loyal to former President Ali Abdullah Saleh since 2014.
Iran's destabilising influence in the Middle East needs to be overcome to end the conflict in Yemen, US Defence Secretary Jim Mattis said today.
The Trump administration's anti-Iran rhetoric reflects the NY businessman's long-held grudge for former President Barack Obama, who threw his support behind talks between Iran and the world powers, which finally yielded a nuclear deal, dubbed the Joint Comprehensive Plan of Action (JCPOA) in 2015.
At the same time, officials have said the USA is considering deepening its role in the conflict by more directly aiding its Gulf allies, which are fighting Iran-supported Houthi militias.
Bulls beat Celtics 101-94; Thomas plays after sister's death
Kerr rested players down the stretch as needed, he mixed Kevin Durant back in after a 19-game absence with a left knee injury. His 27 points, 10 rebounds, 10 assists and 3 steals was impressive but not enough as the Rockets beat the Thunder 102-99.
Under Mr Obama tactical assistance to the coalition was greatly reduced because of concerns over civilian casualties and other disagreements.
The coalition hopes that a successful operation there would force the rebels back to the negotiating table, in a considerably weaker position and thus more amenable to concessions.
Before visiting Riyadh, Mattis said the administration's goal in Yemen was to help arrange a United Nations-brokered peace negotiation.
"It has gone on for a long time, and this is something, with the number of innocent people dying inside Yemen, it has simply got to be brought to an end", Mattis told reporters on his way to Riyadh.
He said the United States would "reinforce Saudi Arabia's resistance to Iran's mischief" and suggested the possibility of President Donald Trump visiting Saudi Arabia.
The goal is for a United Nations team to try to resolve the conflict "politically, as soon as possible", Mattis said.