In 2152, this unnamed Romulan Bird of Prey decloaked and approached the EarthStarfleetstarshipEnterprise as it had unknowingly tress passed on their territory. The Romulan commander hailed (on audio only) and ordered the humans to leave or be destroyed. The Enterprise's translator failed to lock on to the Romulan language. To prove their point the Romulan vessel fired two warning shots at the Earth vessel, which Captain Jonathan Archer ordered Travis Mayweather to activate the Quantum beacons and to avoid hitting any of the cloaked mines that were surrounding the M-class planet. The Romulan vessel that was pursuing them re-cloaked.
This vessel may have been the same one that gathered assistance of another Romulan Bird of Prey to chase the Enterprise away from their system. (ENT: "Minefield")
The novel The Good That Men Do gives the name of one of these vessels as the Praetor Pontilus (β). The prototype cloaking device used by the ship was eventually proven unsuccessful when its use caused an antimatter containment failure and the destruction of the ship later on.