The airline will stop flying to Egypt's capital on Sept. 30 and its last flight to Riyadh, the capital of Saudi Arabia, will be on Sept. 28. However, flights will continue to Jeddah, the gateway to the Saudi holy city of Mecca.
Singapore Airlines said it would refund passengers who hold tickets for flights to the two cities after the flights are suspended. It added that connections to both Riyadh and Cairo are still possible on other airlines via Dubai.
Singapore Airlines flies three times a week to Cairo and Riyadh. The Jeddah flight operates via Riyadh but will stop at Dubai from Oct. 2.
Airlines routinely review their flight operations and pull routes that don't perform well. Singapore Airlines faces tough competition on Middle-Eastern routes from Gulf-based carriers such as Emirates Airline and Qatar Airways. The carrier has focused more on medium-haul flights to China, India, Japan and Australia in recent months.