BEIJING/TAIPEI - Residents in six mainland cities on Saturday were given official permission to visit Taiwan individually under a cross-Straits agreement, adding to the previously approved cities of Beijing, Shanghai and Xiamen.

The move to give approval to the six cities of Tianjin, Nanjing, Chongqing, Hangzhou, Guangzhou and Chengdu is expected to stimulate demand for tourism services on the mainland, as well as boost cross-Strait relations.

"The six cities have a total population of 60 million, and many of their residents have a strong potential for consumption," said Wen Qian, general manager of travel agency GZL in south China's Guangdong province.

Wen said he expects the market for individual tourism, which allows for more flexibility and customization for customers, will grow quickly as a result of the move.

Travel agencies have subsequently called for simplified application procedures.

"High requirements and complicated application procedures might put off many mainland tourists," said Miao Xu from the China Travel Depot.

According to Miao, mainland residents need to obtain two permits, one each from the mainland and Taiwan, before visiting the island. A mainland permit takes about five days to process, while the Taiwan permit takes about ten days.

Taiwan first opened its doors to independent tourists from three mainland cities on June 28 last year. Since then, more than 60,000 residents have traveled there.

An overall ban on traveling to the island was lifted by Taiwanese authorities in July 2008. However, before June 2011, mainlanders could only travel to the island as part of tightly-run tour groups, business trips, academic visits and trips related to family affairs.

The mainland is currently the biggest source of tourists to the island.In 2011, more than 1.78 million mainland residents visited Taiwan, a year-on-year increase of 9.4 percent. Mainlanders accounted for nearly one-third of the 6.08 million visitors the island received last year, according to Taiwanese tourism authorities.