A senior executive of Foxconn on Wednesday said the firm has plans to shift some production lines out of Shenzhen to tap more business opportunities on the mainland and save on production costs.

The new production facilities, however, will not completely replace the Shenzhen production base, where some 420,000 workers are currently employed, the executive, who did not want to be named, told China Daily.

Insiders said many Foxconn production lines will remain in Shenzhen due to the zone's advanced transportation facilities and ideal geographical location.

Foxconn's subsidiary plants in Shenzhen, which assemble iPhones and iPads for Apple, will not be affected by the company's plan to shift north, a source said.

Terry Gou, chairman of Foxconn Technology Group, was reportedly spotted in the company's canteen in Shenzhen on Monday evening.

He told workers that the relocation of some production lines is an "important strategic move" and those who follow the call will receive additional subsidies, the Guangzhou Daily reported on Wednesday.

A worker, surnamed Dong, said many workers have been told they will be relocated.

"But, at the moment, we're still unclear where we will have to move," Dong said.

According to a Xinhua report earlier this week, Foxconn will build a new plant in Zhengzhou, capital of Central China's Henan province.

The company and local officials are working on the details to build the new production facility, which will employ as many as 300,000 employees in the future, the report said.

Zhengzhou has allocated land and launched a massive recruitment drive for the new plant. The first phase of construction will cover 133 hectares, according to the government.

Foxconn also plans to hire more than 100,000 employees for its new Chengdu production base with an investment of US$5 billion, the West China Metropolis Daily has reported, citing an agreement between Foxconn and the local government.

Foxconn has started to hire 1,000 people in Chengdu at a minimum monthly salary of 1,590 yuan (US$235), the Chengdu-based paper said.

In addition, Foxconn's Tianjin base recently contacted the investment department of the Binhai New Area government about expansion, an anonymous official from Tianjin municipal government told China Daily in an earlier interview.

Foxconn is also negotiating with relevant departments in Langfang, Hebei province, to build a plant, according to local media reports.