The Saudi-led coalition fighting in Yemen promised on Thursday (Dec 26) to investigate a military operation this week that the United Nations said killed at least 17 civilians in the latest of three attacks this month on a market.

The coalition has been fighting the Iran-aligned Houthis for almost five years in Yemen, drawing international criticism for civilian casualties from thousands of air strikes.

UN humanitarian coordinator Lise Grande said first reports showed 17 people, including 12 Ethiopians, died and 12 people were injured in Tuesday's strike on the al-Raqw market in Saada, an area near the Saudi border controlled by the Houthis.

A Nov 20 attack there killed or injured 28, and another on Nov 27 killed or injured 32, according to the United Nations.

Grande did not single out the coalition, but said the market attacks were deeply troubling. "The parties responsible for this, and other atrocities, must be held accountable," she said.

Houthi-controlled al-Masirah TV said Tuesday's incident was a result of artillery shelling from across the Saudi border.

Coalition spokesman Colonel Turki al-Malki, in a statement carried by Saudi state news agency SPA, said an initial review of the operation in Saada indicated possible "incidental losses and collateral damage".

The case has been referred to the coalition's incident assessment team in keeping with its commitment to international humanitarian law, Malki added.

Last year, the Saudi-led coalition accepted that an air attack killing dozens, including children on a bus, was wrong and pledged to hold accountable those responsible.

The United Nations has been trying to broker an end to the war, which has killed tens of thousands of people and pushed millions to the brink of famine.

The Houthis, who control most large urban centres, deny they are puppets of Iran and say their revolution is against corruption. The Saudi-led coalition backs the internationally recognised government of Abd-Rabbu Mansour Hadi that was ousted from power in the capital, Sanaa, by the Houthis in late 2014.

Saudi Arabia has recently stepped up informal talks with the Houthis on a ceasefire.