Saudi Arabia’s General Authority of Civil Aviation revoked on Tuesday all operating licenses granted to Qatar Airways as part of the Kingdom’s severing of diplomatic ties with its neighbor.

It also announced that all of its offices in Saudi Arabia will be closed within 48 hours, reported the Saudi Press Agency (SPA).

“We urge all passengers who purchased tickets to or from Qatar to check the airline website or contact their travel agent online for a refund,” said the General Authority of Civil Aviation in a statement.

Saudi Arabia has also closed its border with Qatar, effectively blocking food imports and a segment of the country’s exports after Riyadh accused Doha of supporting extremism and terrorism.

Qatari share prices closed down 7.58 percent on Monday after five Arab countries — Saudi Arabia, the UAE, Egypt, Bahrain and Yemen — announced they were cutting diplomatic ties with the emirate.

Saudi Arabia, the UAE, Bahrain and Egypt announced the suspension of all flights to and from Qatar as of Tuesday morning.

The Gulf states have also ordered Qataris to leave within 14 days and banned their own citizens from traveling to Qatar.

On Monday, Qatar Airways suspended all flights to Saudi Arabia, the United Arab Emirates, Egypt and Bahrain until further notice.

In a statement issued on its website, the carrier said the suspension of its flights will go into effect Tuesday. It is offering customers affected by the decision a refund on unused tickets.

The decision comes after major Gulf carriers, including the Middle East’s largest carrier in Dubai, Emirates Airways, suspended flights to Qatar.

The route between Doha, Qatar and Dubai is popular among business travelers and both are major transit hubs for travelers between Asia and Europe.