Riyadh, Asharq Al-Awsat—Saudi-led airstrikes against the Iran-backed Shi’ite Houthi movement in Yemen have successfully cut off air supply lines to the movement from Tehran, Saudi Arabia’s Defense Ministry said on Sunday.

In his daily briefing on the progress of the air assaults—dubbed Operation Decisive Storm—Defense Ministry spokesman Brig. Ahmed Bin Hassan Assiri told reporters the Houthis had used a recent deal signed between Yemen and Iran’s civil aviation authorities to gain military supplies from the Islamic Republic.

Yemen and Iran’s civil aviation authorities signed the agreement in late February, following the Houthi coup, to operate 14 direct flights between both countries, via state carrier Yemen Airways and Iranian private airliner Mahan Air.

Assiri said the Houthis had amassed a large amount of weapons and ammunition from Iran since the deal was signed, but that these supply lines had now been successfully cut off, with weapons storage facilities also targeted throughout the country.

The border between Saudi Arabia and Yemen had now also been secured, he said.

He added however that the operation to target Houthi military supplies stored throughout Yemen was ongoing and remained difficult as the group had placed many of their supplies near residential areas.

The Arab-wide, Saudi-led airstrikes are particularly focusing on the Houthis’ anti-aircraft and ballistic capabilities, he added.

This comes as Operation Decisive Storm reaches its fifth day and regional allies continue to bomb Houthi targets in Yemen. Warplanes from Egypt, Morocco, Jordan and Sudan, as well as Gulf Cooperation Council (GCC) countries the UAE, Kuwait, Bahrain and Qatar, are also taking part in the operation.

Speaking to Asharq Al-Awsat on Sunday, Qatari Defense Minister Maj. Gen. Hamad Bin Ali Al-Attiyah said Gulf countries had no choice but to enter the operation after the Houthis refused repeated calls to return to the negotiating table.

“The Houthis insisted on continuing their plot, which completely sidelines the legitimate and elected political authority in Yemen and threatens the security and stability of the country,” he said.

“Even this wasn’t enough, though, and the movement also began threatening the security and stability of other regional countries, including Saudi Arabia, and this is what pushed the GCC countries to take the decision to enter military operations in Yemen in order to defend the region.”

Regarding Iran, which is backing the Houthi coup in Yemen, Attiyah said that GCC countries deal with the Islamic Republic “on the basis of mutual respect and the non-interference in the internal affairs and sovereignty” of other countries.

He also dismissed talk of a sectarian, Sunni–Shi’ite basis for the current offensive, saying that Shi’ites were an “essential part of the makeup of the region” and that religious affiliation should have no bearing on citizenship.

Attiyah also said it was unlikely the current air offensive would be beefed up with ground troops at the current time, though he said that should a “political decision” be taken from Arab countries to enter Yemen with boots on the ground, Doha would be ready to offer its assistance and that its armed forces would be “at the service” of its allies in the region.

Nasser Al-Haqbani contributed additional reporting from Riyadh.