Treaty of Algeron

The Treaty of Algeron was a peace treaty signed between the United Federation of Planets and the Romulan Star Empire in 2311, following the events of the Tomed Incident. The treaty reinforced and re-defined the Romulan Neutral Zone, and made clear that any violations of the Zone without adequate notification, by either side, would be considered an act of war.

The use of a cloaking device by a Federation starship is strictly prohibited by this treaty. Admiral Erik Pressman attempted to circumvent this clause in 2358 with the test of an interphase cloaking device developed by Starfleet Intelligence (possibly the covert Section 31) aboard the USS Pegasus.

A Treaty signed between the Federation and the Romulan Empire in 2371 waived the Treaty of Algeron and enabled Starfleet to install and operate a cloaking device.