Yemenis attend a rally protesting the recent deployment of U.S. forces there, amid the ongoing conflict between an Arab military coalition against Houthi rebels and al-Qaeda fighters. YAHYA ARHAB/EUROPEAN PRESSPHOTO AGENCY

Saudi Arabia will send troops into Sanaa, the Yemeni capital, if peace talks between the Saudi-backed government and Shiite rebels fail, a military spokesman said Wednesday, raising the specter of extended conflict.

Brig. Gen. Ahmed Asiri, a spokesman for the Saudi-led military coalition that has been fighting Houthi rebel forces since last year, said that Saudi Arabia hoped that peace talks in Kuwait, already strained by ongoing violence on the ground, would succeed.

“If not, … today we have troops around the capital, and we will get in, because the goal should be achieved, the goal which is securing Yemen,” Asiri told reporters during a visit to Washington. “Securing Yemen doesn’t mean that we will tolerate to have a militia … controlling ballistic missiles, artillery, etc., and threatening our border and threatening the area.”

But Saudi Arabia would face a major challenge in trying to advance local troops or members of its mostly Arab military coalition into the Sanaa area, populated by supporters of the Houthi movement and former President Ali Abdullah Saleh.

Asiri’s comments came several days after U.S. officials revealed that they had placed a small team of U.S. advisers on the ground around the Yemeni port city of Mukalla, where they are supporting operations in a parallel campaign by Emirati troops fighting alongside Saudi forces against al-Qaeda in the Arabian Peninsula (AQAP).

When Yemeni and Persian Gulf forces pressed into Mukalla last month, it was a milestone in the country’s multi-sided civil war, expanding their campaign to launch a major offensive against a group that U.S. officials identify  as the most lethal al-Qaeda affiliate.

The action against AQAP has also drawn the United States deeper into the conflict. The small advisory operation marks the first U.S. military presence since the rebels’ takeover of Sanaa in late 2014 prompted Washington to pull remaining American personnel from Yemen and end a long-standing training program for local forces.

Asiri said Saudi and Emirati Special Operations forces, about a company-size unit of each, joined troops loyal to the Yemeni government in fighting the militants in Mukalla. He declined to say how many Saudi troops had been on the ground but said most of them had been withdrawn after the fighting in Mukalla subsided. In addition to the foreign troops in Mukalla, on Yemen’s southern coast, 300 Sudanese troops are in Aden, another important port city to the west.

Asiri said the Mukalla operation was just “one step” required against AQAP, which had retreated into remote areas where it is difficult to track, adding that Yemeni forces would need to reassert government control of those areas. “The objective is, once you free the zone, you put the army on the ground, the Yemeni army on the ground, and you start providing services,” he said.

The expanded operations against AQAP take place as the United Nations struggles to bring about progress in the Kuwait peace talks. This week, Houthi leaders accused Saudi Arabia of violating a recently announced truce. Asiri, meanwhile, said that rebels had fired two Scud missiles at a Saudi city this week.

“We cannot leave Yemen in a gray area without having a final result,” he said. “Otherwise, we will see the Libyan model in Yemen.”

The general defended Saudi Arabia’s management of its air campaign against the Houthi rebels, saying that strikes were conducted to the standard of NATO operations. “We take all the measures to conduct surgical airstrikes,” he said.

The United Nations has accused the Saudi-led coalition of being responsible for twice the number of civilian casualties as other combatants in Yemen. Asiri said that Saudi and allied forces systematically investigated allegations of civilian casualties but were hindered by a lack of access to Houthi-controlled areas. He did not provide a number for how many of those allegations had been verified.

The United Nations says the conflict has killed more than 6,000 people and triggered a severe humanitarian crisis in an already poor country.