Neither company has disclosed the size of their businesses in China, where since 2009 they have mainly handled documents and packages to and from overseas. But both companies have cited China as one of their fastest-growing markets.
UPS and FedEx had to reapply for licenses to offer domestic B2C services after the law changed. In 2012, the pair were granted their first five and eight respectively. FedEx was able to continue offering services by entering joint ventures with local peers.
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But even at full strength, UPS and FedEx still face daunting competition in state-backed China Post and large, privately run rivals such as Shentong Express and S.F. Express.
Seeming willingness among private services to cut margins to win customers also constitutes a challenge. Deutsche Post's DHL courier service pulled out of its money-losing China domestic delivery business in 2011 citing a lack of cost advantage.
UPS's Lane said allowing greater competition would help improve standards across China's logistics industry.
"With greater competition there's always the beneficial effect of raising the professionalism and quality of services that consumers come to expect," Lane said.