The coalition called for an independent investigation into the incident.
Pictures printed on the front pages of Gulf dailies showed the foreign troops and local tribesmen planting the flags of the United Arab Emirates, Bahrain and Saudi Arabia over the dam.
More than 130 people have died in the suspected air strike in Yemen, according to latest death toll.
Initially reported as a “mistaken” air strike by the Saudi-led coalition, the USA backed group is now denying its role in the civilian tragedy as a coalition spokesperson “suggested local militias may have been responsible” for targeting the party, which included many women and children.
Monday’s bloody attack followed an assault against a residential area in Hajjah province on Sunday by Saudi-coalition helicopter gunships that resulted in the deaths of 28 civilians and wounded 17 others.
Saudi military spokesman Brigadier-General Ahmed al-Assiri said on Tuesday that the airstrike accusation was “completely false”.
Saudi Arabia’s official news agency carried no comment on the reports of the deaths in al-Mokha, but the spokesman for the Arab coalition rejected the claims of air attacks in the area.
“The coalition knows its responsibility and will always acknowledge a mistake if we make it. Take into consideration the chaotic situation in Yemen, with several armed elements and forces active around the country”.
He added that the coalition would concede a mistake if it made one but he said the situation on the ground is chaotic and civilians may not be able to differentiate between cannon, mortar and rocket fire.
The event focused on exposing the crimes committed by the Houthi militias and the forces of Ali Abdullah Saleh who was deposed as President in 2012 after they took power by force occupied Yemeni cities and institutions and removed the legitimate and elected government of President Hadi.
Yemen relies on imports, but a near-total blockade led by Saudi Arabia has slowed shipments to the Arabian Peninsula country to a trickle.
ADEN, Yeman _ As Saudi soldiers drive armored vehicles around Aden, the port in southern Yemen they helped recapture from rebels, young men clap and children flash the V-for-victory sign.
Six months of civil war and hundreds of coalition air strikes have killed more than 5,400 people in Yemen, according to the United Nations, and exacerbated already widespread hunger and suffering.