Saudi authorities said on Monday ‌they were extending the suspension of operations at the international airport in the capital, Riyadh, after deadly weekend attacks by Yemen’s Iran-aligned Houthis.

Operations at King Khalid International Airport, Saudi Arabia’s second-busiest airport after Jeddah, were suspended ​to “allow for the completion of procedures to ensure the safety and operational readiness of ​the airport’s facilities”, the Saudi civil aviation authority said in a statement.

The ⁠airport has been shut since an attack on Saturday that killed 13 people and wounded ​more than 300, the deadliest in the kingdom in more than a decade. On Sunday, another ​attack killed one person and injured nearly a dozen others.

The attacks marked one of the most significant disruptions to Saudi aviation in years, adding to pressures on an industry already grappling with conflict across the Middle ​East.

The airport cancelled 99.7% of all scheduled flights on Sunday, according to aviation analytics firm ​Cirium. An air traffic tracker from Flightradar24 showed no planes over the city.

The disruption has forced airlines across ‌Europe ⁠and Asia to suspend services, while the Federal Aviation Administration advised US carriers on Sunday to exercise caution when flying to or over Saudi Arabia.

Lufthansa Group has cancelled all flights to Riyadh until October 16, while Air France-KLM has cancelled all flights to Riyadh until October 16, while Air France-KLM has extended a previous suspension of services to and from the ​Saudi capital until the ​end of the ⁠month.

Abu Dhabi’s Etihad Airways was among the airlines that further extended Saudi flight cancellations, affecting around 20 flights to Riyadh, Jeddah and Dammam on ​Monday and Tuesday.

The escalation with the Houthis has raised concerns over ​the broader ⁠economic impact. Saudi Arabia’s real GDP is projected to contract by 3.6% this year, reflecting a combination of factors including lower oil activity.

The attacks have put events scheduled in Riyadh this month under pressure, including ⁠the ​kingdom’s flagship investment conference and the WPC Energy Congress, ​where several top oil executives were dropped from the programme.