A departure time flight board displays various cancellations as passengers stand nearby at Ben Gurion International airport in Tel Aviv July 22, 2014. The Federal Aviation Administration (FAA) banned U.S. carriers from flying to or from Ben Gurion Intern
A departure time flight board displays various cancellations as passengers stand nearby at Ben Gurion International airport in Tel Aviv July 22, 2014. The Federal Aviation Administration (FAA) banned U.S. carriers from flying to or from Ben Gurion International Airport, after a rocket fired from Gaza struck near the airport's fringes, injuring two people. European airlines including Germany's Lufthansa, Air France and Dutch airline KLM said they were halting flights there too. Israel's flagship carrier El Al continued flights as usual. REUTERS/Siegfried Modola (ISRAEL - Tags: CONFLICT POLITICS CIVIL UNREST TRANSPORT) REUTERS/Siegfried Modola

Travelers going in and outside of China are being advised to brace for potential delays and worst, flight cancellations in the next three to four weeks. The country's People's Liberation Army is currently conducting military drills over the East China Sea, thus imposing "air traffic restrictions."

Among the airports affected will be Shanghai International Airport Co Ltd and 11 other airports in east China.

State broadcaster China Central Television reported the drills are expected to last until August 15.

On Monday, around 200 flights were canceled at Pudong and Hongqiao, two airports in Shanghai, while another 120 flights were delayed for more than two hours.

CCTV, on its Weibo account, China's equivalent of Twitter, shared a widely circulated memo that showed China's civil aviation authority requesting global airlines to reduce flight frequency to eastern China by 25 per cent in the coming weeks.

"The following 12 airports will experience massive delays for 26 days! Fliers, bring snacks and water!" the CCTV post said. "From July 20 to August 15, operations of these airports -- including Shanghai Hongqiao, Shanghai Pudong, Nanjing, Hangzhou, Hefei, Jinan, Wuxi, Ningbo, Qingdao, Lianyungang, Zhengzhou and Wuhan -- will be affected by high-frequency exercises conducted by another party. All airlines are requested to reduce flights by 25 per cent and fliers are expected to face delays."

State-run Xinhua News Agency reported People's Liberation Army started on July 15 what would be three months of live-fire drills in six regional military commands. Some of these training sessions, the report said, would be conducted under a "complex electromagnetic environment."

The drills include live-fire exercises with tanks in night conditions and foreign terrain aimed to temper combat capabilities under complicated conditions, Hong Kong newspaper Ming Pao reported. Takeoff formations and testing lifesaving capabilities in complex sea environments were likewise being done by the PLA Air Force.

Portal WantChinaTimes.Com reported at least 65 planes delayed or canceled on Saturday flights between Hong Kong and Shanghai. Over 10,000 passengers have been affected.