BEIJING, June 17  -- An application by three leading global shipping firms to build an operational alliance has been rejected by China due to monopoly concerns, the Ministry of Commerce said on Tuesday.

Major container shipping lines, Maersk Line, Mediterranean Shipping Company and CMA-CGM, in October 2013 agreed to establish an operational alliance named P3 Network to provide customers with more frequent and flexible services. The network would involve three trade lanes: Asia-Europe, Trans-Pacific and Trans-Atlantic.

The network was expected to start operation in the second quarter of 2014, but will be subject to approvals by various authorities, including the European Union, United States and China.

The ministry supports companies to sharpen their competitive edge, but when firms try to improve market share through a "concentration of undertakings", it should be carefully studied, said a statement on the ministry's website.

The three operators handed in the application to the ministry on September 18, 2013 for a "concentration of undertakings" anti-monopoly probe.