Air China, one of China's largest airline companies and the national flag carrier, will launch and resume four international routes starting from Sunday, better serving the Belt and Road Initiative and promoting opening-up, according to the company on Tuesday.

The newly opened routes are Beijing-Riyadh and Beijing-Dhaka. While the other two, Beijing-Madrid-Sao Paulo and Beijing-Madrid-Havana, will also resume. By then, Air China's route network will again cover all six continents.

This year, Air China has continued to improve its international route network, striving to promote the resumption and increase of international flights.

According to the company, the capacity of international and regional routes during the summer and autumn season, which began on March 30, has resumed to 84 percent of the level in 2019, with the capacity input for European routes exceeding 110 percent of the 2019 level.

With the opening and resumption of the four routes, the company will operate a total of 452 domestic, international and regional routes, including 112 international and regional routes. The route network covers 64 cities in 43 countries and regions.

The resumption of the Beijing-Madrid-Sao Paulo route from Sunday will be the first route operated by a Chinese airline to reach Brazil, spanning three continents and ranking as one of the world's longest routes.

The resumption of the Beijing-Madrid-Havana route from May 17 is the only route between China and Cuba.

The newly opened Beijing-Riyadh route, which will begin on May 6, will open an air passage for China and the Middle East, especially Saudi Arabia.

The upcoming Beijing-Dhaka route, scheduled to open in June, will create a more convenient air bridge between China and Bangladesh.

China's civil aviation sector has been accelerating the resumption of international passenger flights since the summer season started in the end of last month.

According to the Civil Aviation Administration of China, the new season, which began on March 30 and runs through Oct 26, will see over 12,600 weekly international passenger flights operated by 122 Chinese and international airlines. They will link China to 66 countries, representing a significant increase from previous periods.

The administration said it will guide all airlines to continue increasing capacity and adding more flight routes between China and countries involved in the Belt and Road Initiative to meet travelers' needs and better serve national strategies.