BEIJING  -- Airlines on both sides of the Taiwan Strait are busy preparing for Friday's landmark launch of weekend charter flights.

Six airlines from the mainland and five from Taiwan will operate the 18 return flights on the first day of the weekend service.

Under an agreement signed last month, 36 return flights will operate every weekend, Friday to Monday, divided evenly between mainland and Taiwan airlines.

The first flight from the mainland to Taiwan will leave Guangzhou in southern Guangdong Province at 6:30 a.m. on Friday and head for Taipei, operated by China Southern Airlines (CSA).

The first flight from Taiwan to the mainland, operated by Taiwan-based Mandarin Airlines, is to take off from Taoyuan Airport near Taipei at 3:30 a.m. bound for Nanjing in eastern Jiangsu Province.

CSA has prepared special programs to tell passengers about Taiwan, which will be broadcast en route to Taiwan. On the way back, passengers will watch programs depicting tourist sites, foods and customs in the mainland, said a CSA source.

The in-flight entertainment service will add songs in the Minnan and Hakka dialects, which are commonly spoken in Taiwan, as well as Taiwan movies, the source said.

Air China will send its most experienced crew on the flights. All have flown across the Strait before, the company said in a press release.

According to Taiwan media, all five Taiwan airlines planned to offer Taiwan specialties as part of the food service and some will hand out small gifts to passengers to mark the day.

Taiwan media also reported that all airports were ready to receive the charter flights and some planned ceremonies for the first day of service.

The two sides signed the agreement to begin these flights during a meeting between the mainland-based Association for Relations Across the Taiwan Straits and the Taiwan-based Straits Exchange Foundation on June 13.

Previously, services only ran during major Chinese festivals. Charter flights started for the Spring Festival, a major event for Chinese family reunions, in 2003.

In 2006, service was expanded to three other major Chinese holidays: the Qingming (Tomb Sweeping) Festival, the Dragon Boat Festival and the Mid-Autumn Festival.

On Friday, the first group of 760 mainland tourists will also start a historic journey to Taiwan and stay for 10 days. They will take the new weekend flights.