The Saudi-led coalition fighting Iran-backed Houthi militias in Yemen said on Tuesday that a ceasefire had begun at noon (0900 GMT) as scheduled.

Coalition spokesman Brigadier General Ahmed al-Assiri confirmed that the truce had taken effect. The militia forces have yet to say if they will abide by the ceasefire.

“The command of the coalition forces announces a ceasefire as of 12 P.M. Sanaa time ... while retaining the right to respond to any breach of the ceasefire,” the alliance said in a statement on the Saudi state news agency, SPA.

“The ceasefire (will last) for a period of seven days starting from the 15th to the 21st of December in conjunction with the launch of consultations, and will be renewed automatically in the event of the commitment of the other party,” it said.

The coalition opened a military campaign in late March to stop Houthi militias from taking complete control of Yemen after they seized the capital, Sanaa, last year. The Houthi militias accuse the coalition of launching a war of aggression.

The campaign has brought embattled Yemeni President Abdrabbu Mansour Hadi little closer to running a united country again.

Meanwhile, Yemen’s Prime Minister Khaled Bahah on Tuesday called on Houthis to lay down their weapons, as a ceasefire in his war-wracked country came into force.

“We need to restore the country,” Bahah said in the Qatari capital Doha.  “We need the Houthis to surrender their weapons and arms and leave the government institutions to restore legitimacy.”

Bahah was delivering a speech at Qatar University coinciding with the start of a seven-day ceasefire as U.N.-brokered peace talks opened in Switzerland.

In October, Bahah escaped unharmed after a deadly rocket attack on a hotel in Yemen’s main southern city of Aden.

However, Houthis attacked pro-government forces in the eastern Maarib province, killing 15 fighters, military sources and medics said Tuesday.

The Iran-backed rebels “violated the truce” and attacked positions in Mas, in province's west, killing 15 people and wounding 20 more, a loyalist military source told AFP.

Medical sources in Maarib confirmed the toll.

Reuters, AFP