The Justice Department sued to block Hewlett Packard Enterprise's $14 billion acquisition of rival Juniper Networks on Thursday, the first attempt to stop a merger by a new Trump administration that is expected to take a softer approach to mergers.

The U.S. Department of Justice has sued to block Hewlett Packard Enterprise's $14 billion deal to acquire networking gear maker Juniper Networks, arguing that it would stifle competition, according to a complaint filed on Thursday.

Hewlett Packard Enterprise shares are trading lower Thursday after the U.S. Department of Justice (DOJ) filed an antitrust lawsuit to block its proposed $14 billion acquisition of Juniper Networks.