Foreign companies will continue to be barred from delivering express letters in China's domestic market based on a new law approved Friday, after major global express-delivery companies have been lobbying Beijing for years to lift the restrictions.

Foreign companies will be limited to delivering express packages domestically, and can only send express letters internationally, Wang Yuci, vice director of the State Post Bureau, told Dow Jones Newswires Friday on the sidelines of a press briefing.

Chinese companies, both state-owned China Post and privately operated ones, will carry out the business of domestic express delivery of letters, according to the revised postal law.

Under to the original law, mail delivery was monopolized by China's official postal services. There was no separate stipulation over express delivery services.

Companies such as FedEx Corp.(FDX) and United Parcel Service Inc.(UPS) have been lobbying Beijing for years as it worked on the new law governing mail delivery, arguing the restriction prevents them from competing in the country's rapidly expanding market for delivering documents.

China's express delivery business had revenue of more than CNY10 billion in the first quarter, more than a third of the country's total postal revenue of CNY25.96 billion, according to latest data from the State Post Bureau.

China's revised postal law will take effect October 1. It was approved by the Standing Committee of the National People's Congress, the country's legislature which meets once every two months.

The ban over foreign companies in the domestic letter express delivery market is in line with China's commitments to the World Trade Organization made in 2001, said He Yongjian, an official with the Legislative Affairs Commission of the Standing Committee of the National People's Congress.

-Liu Li contributed to this story, Dow Jones Newswires; 8610 6588 5848; li.liu@dowjones.com